The rete testis is the network of interconnecting tubules where the  straight seminiferous tubules  (the terminal part of the  seminiferous tubules ) empty. It is located within a highly vascular  connective tissue  in the  mediastinum testis . [ 2 ]  The  epithelial cells  form a single layer that lines the inner surface of the tubules. These cells are  cuboidal , with  microvilli  and a single  cilium  on their surface. [ 3 ]


In the  development of the urinary and reproductive organs , the  testis  is developed in much the same way as the  ovary , originating from  mesothelium  as well as  mesonephros . Like the ovary, in its earliest stages it consists of a central mass covered by a surface epithelium. In the central mass, a series of cords appear. These cords run together toward the future  hilum  and form a network that ultimately becomes the rete testis.


It appears the function of the rete testis is to mix the sperm as they leave the seminiferous tubules. Sperm leave the seminiferous tubules in the dilute secretions of Sertoli cells. The rete testis does modify the luminal fluids with a limited amount of secretion and reabsorption, but their primary function is to mix and transport the sperm into the efferent ductules, where the major function is reabsorption of about 95% of the fluid, which increases the sperm concentration prior to entering the epididymis.


Rete tubular ectasia  is a disorder of the rete testis characterized by multiple benign  cysts .


English uses the  Neo-Latin  name for the structure, which simply means " network  of the  testis ".


The  seminal tract  is a part of the  male reproductive system  and consists of  seminiferous tubules  ( tubuli seminiferi recti ,  rete testis ,  efferent ducts ),  epididymides   ( appendix ),  Vas deferens  ( ampulla ) and  ejaculatory ducts .


The  septa testis  are fibrous partitions of the testis dividing the testis into compartments - the  lobules of the testis . The septa are formed by extensions of the  tunica albuginea  - the dense fibrous connective tissue surface covering of the testis - into the substance of the testis. The septa converge towards the  mediastinum testis . [ 1 ]


In  human male   anatomy , the  septum of the penis  or  penile septum  refers to the  fibrous  junction ( septum ) between the two  corpora cavernosa  of the  human penis . The  tunica albuginea  of the penis forms a thick fibrous coat to the  spongy tissue  of the corpora cavernosa and  corpus spongiosum . [ 1 ]  The two corpora cavernosa are surrounded by a strong fibrous envelope consisting of superficial and deep fibers. The superficial or outer fibers are  longitudinal  in direction, and form a single tube which encloses both corpora; the deep or inner fibers are arranged circularly around each corpus and meet in the center. By their junction in the  median plane , the inner fibers form the intercavernous septum of the penis. [ 2 ] [ 1 ]


This septum is composed of multiple strands of  connective tissue , similar to that of the  tunica albuginea . [ 3 ]  It is thick and complete behind, where the corpora cavernosa become independent and form separate  crura , [ 3 ]  but it is imperfect in the front, where it consists of a series of vertical bands arranged like the teeth of a comb; it is therefore named the  septum  pectiniforme  ( pectinate  septum). [ 4 ]


This article incorporates text in the  public domain  from  page 1248  of the 20th edition of   Gray's Anatomy   (1918)


A  Sertoli cell nodule  is a  benign   proliferation  of  Sertoli cells  that arises in association with  cryptorchidism  (undescended testis). [ 1 ]   They are not composed of a clonal cell population, i.e.  neoplastic ; thus, technically, they should not be called an  adenoma . [ 2 ]


Sertoli cell nodules are unencapsulated nodules that consist of: [ 2 ] [ 3 ] [ 4 ]


Sialuria  is a group of disorders resulting in an accumulation of free  sialic acid . [ 1 ]  One type, known as the Finnish type or  Salla disease  has been described in northeastern Finland and is due to a mutation in gene SLC17A5 on chromosome 6q4-15. [ 1 ]  The "French type sialuria" ( Online Mendelian Inheritance in Man  (OMIM):  269921 ), [ 1 ]  is a very rare condition presenting in infancy with  failure to thrive ,  yellowish skin ,  large liver ,  low blood count , recurrent chest infections,  bowel upsets , dehydration and characteristic facial features. [ 2 ] [ 3 ] [ 4 ]


Spermaturia  is condition characterized by the presence of  sperm  in the  urine . [ 1 ]


It can be observed in males of other species and then sometimes diagnosed in  veterinary medicine . [ 2 ]  The cause is most often a  retrograde ejaculation . It may be  physiological  during  urination  after  coitus  (postcoital urination). [ citation needed ]


An irrational belief that one is experiencing spermaturia is a common symptom of  Dhat syndrome . [ 3 ]


The  subcutaneous tissue of penis  (or  superficial penile fascia ) is continuous above with the  fascia of Scarpa , and below with the  dartos tunic  of the  scrotum  and the  fascia of Colles .


It is sometimes just called the "dartos layer". [ 1 ]


It attaches at the intersection of the body and glans. [ 2 ]


The term "superficial penile fascia" is more common, but "subcutaneous tissue of penis" is the term used by  Terminologia Anatomica .


A  supernumerary  kidney  is an additional kidney to the number usually present in an organism. This often develops as the result of splitting of the nephrogenic  blastema , or from separate  metanephric blastemas  into which partially or completely reduplicated ureteral stalks enter to form separate capsulated kidneys; in some cases the separation of the reduplicated organ is incomplete (fused supernumerary kidney).


Less than a hundred cases are known of one or two supernumerary kidneys.


The  supravaginal portion of the cervix  (also known as the  uterine portion of the cervix ) is separated in front from the  bladder  by fibrous tissue ( parametrium ), which extends also on to its sides and lateralward between the layers of the  broad ligaments .


The  uterine arteries  reach the margins of the cervix in this fibrous tissue, while on either side the  ureter  runs downward and forward in it at a distance of about 2 cm. from the cervix.


Posteriorly, the supravaginal cervix is covered by peritoneum, which is prolonged below on to the posterior vaginal wall, when it is reflected on to the  rectum , forming the  recto-uterine pouch .


It is in relation with the rectum, from which it may be separated by coils of  small intestine .


This article incorporates text in the  public domain  from  page 1259  of the 20th edition of   Gray's Anatomy   (1918)


The  theca externa  is the outer layer of the  theca folliculi . It is derived from connective tissue, the cells resembling  fibroblasts , and contains  abundant  collagen . [ 1 ]  During ovulation, the surge in  luteinizing hormone  increases  cAMP  which increases  progesterone  and  PGF2α  production. The PGF2α induces the contraction of the  smooth muscle  cells of the theca externa, increasing intrafollicular pressure. This aids in rupture of the mature  oocyte , or immature oocyte at the germinal vesicle stage in the canine, along with  plasmin  and  collagenase  degradation of the follicle wall.


Theca interna  cells express  receptors  for  luteinizing hormone  (LH) to produce  androstenedione , which via a few steps, gives the  granulosa  the precursor for  estrogen  manufacturing. [ 1 ]


After rupture of the mature  ovarian follicle , the theca interna cells differentiate into the  theca lutein cells  of the  corpus luteum . Theca lutein cells secrete  androgens [ 2 ]  and  progesterone . Theca lutein cells are also known as small luteal cells. [ 2 ]


The  thin segment  is a part of the renal tubule found between the  proximal  and  distal tubules . The renal tubule and the  renal corpuscle  together comprise the  nephron . [ 1 ]


The thin segment is described as a U-shaped band, consisting of the two continuous parts:


Both limbs of the loop of Henle are lined with the  simple squamous epithelium . [ 2 ]  Their main function is to regulate the levels of  water  and solutes in the primary  urine . The  basement membrane  of the thin limb in humans has very uniform nodular thickenings that form a network that surrounds the tubule and acts as a support structure that is homologous to the collenchyma in  plants . Smith, RA et al. (Arch Pathol Lab Med Vol 108, May 1984) have designated these nodules "Belliveau Bodies" after Robert Belliveau the pathologist who originally described these structures. [ 3 ]


Tight hymenal ring  is a disorder of the  hymen , characterized by a rigid hymen and tight  introitus , whether acquired or congenital. It excludes an  imperforate hymen .


The individual with tight hymenal ring might face difficulty in inserting a tampon into the  vagina  or having intercourse. The condition can be relieved by  outpatient surgery  or manual dilation. [ 1 ]


From the internal surface of the fibrous envelope of the  corpora cavernosa penis , as well as from the sides of the septum, numerous bands or cords are given off, which cross the interior of these corpora cavernosa in all directions, subdividing them into a number of separate compartments, and giving the entire structure a spongy appearance.


These bands and cords are called the  trabeculae of corpora cavernosa of penis , and consist of white fibrous tissue, elastic fibers, and plain muscular fibers. In them are contained numerous arteries and nerves.


The component fibers which form the trabeculae are larger and stronger around the circumference than at the centers of the  corpora cavernosa ; they are also thicker behind than in front.


The interspaces (cavernous spaces), on the contrary, are larger at the center than at the circumference, their long diameters being directed transversely.


They are filled with blood, and are lined by a layer of flattened cells similar to the endothelial lining of veins.


This article incorporates text in the  public domain  from  page 1250  of the 20th edition of   Gray's Anatomy   (1918)


The fibrous envelope of the  corpus cavernosum urethrae  is thinner, whiter in color, and more elastic than that of the  corpora cavernosa penis . It is called the  trabeculae of corpus spongiosum of penis .


The trabeculae are more delicate, nearly uniform in size, and the meshes between them smaller than in the corpora cavernosa penis: their long diameters, for the most part, corresponding with that of the penis.


The external envelope or outer coat of the corpus cavernosum urethrae is formed partly of unstriped muscular fibers, and a layer of the same tissue immediately surrounds the canal of the  urethra .


Trigonitis  is a condition of  inflammation  of the  trigone region  of the  bladder . It is more common in women. [ 1 ]


The cause of trigonitis is not known, and there is no solid treatment.   Electrocautery  is sometimes used, but is generally unreliable as a treatment, and typically does not have quick results.  Several drugs, such as  muscle relaxants ,  antibiotics ,  antiseptics  such as  Urised , have varied and unreliable results. Other forms of treatment include  urethrotomy ,  cryosurgery , and  neurostimulation . [ citation needed ]


The  tunica albuginea  is a layer of condensed  fibrous tissue  on the surface of the  ovary .


The tunica albuginea is composed of short  connective tissue  fibers. It is located immediately inside the surface  epithelium  (previously known as  germinal epithelium ) which is continuous with the  peritoneum . It is  non-vascularised . [ 1 ]  It is thinner than the  tunica albuginea of the testis , and its thickness varies across the  ovary . [ 1 ]


The tunica albuginea is formed late in  prenatal development . [ 1 ]  It buds off from mesonephric stroma. [ 1 ]


The  tunica albuginea  is a dense, [ 1 ] [ 2 ]  blue-white [ 3 ]  layer of  fibrous tissue  surrounding the  testis . [ 1 ] [ 4 ]  It is the middle of three envelopes forming the capsule of the testis; it is deep to the visceral layer of  tunica vaginalis , and superficial to the  tunica vasculosa testis (vascular layer of testis) . [ 5 ]


The connective tissue of the tunica albuginea testis extends into the substance of the testis to form fibrous partitions - the  septa testis . [ 1 ]  At the posterior aspect of the testis (where the serosa of testis is deficient to allow for the attachment of the  epididymis ), the tunica albuginea extends into the testis to form the  mediastinum testis . [ 5 ]


It is thicker than the  tunica albuginea of the ovary . [ 6 ]


It is composed of bundles of white fibrous  connective tissue  (from which it derives its name  albuginea ) which interlace in every direction. [ 7 ]


The  tunica vasculosa testis  ( vascular layer of testis ) is the inner-most of the three layers that form the capsule of the  testis . It consists of a vascular plexus and  loose connective tissue . It extends into the testis itself to line the surfaces of individual  septa of testis . [ 1 ]


Related to the  urinary bladder , anteriorly there are the following folds:


This article incorporates text in the  public domain  from  page 1231  of the 20th edition of   Gray's Anatomy   (1918)


Umbilical-urachal sinus   is a  congenital disorder  of the  urinary bladder  caused by failure of obliteration of proximal or distal part of the  allantois , and the presentation of this anomaly is more common in children and rarer in adults. [ 1 ] [ 2 ] [ 3 ]  In contrast to a  urachal diverticulum  (patent urachus), it is characterised by focal dilatation of the umbilical portion of the remnant urachal tract.


It is thought have been first described by Cabriolus in 1550. [ 4 ]


A  urachal diverticulum  (also  vesicourachal diverticulum ) is a  congenital disorder  caused by the partial persistence of the  allantois . The allantois, which later becomes the  urachus , connects an embryo's  bladder  to the  yolk sac . Normally, the urachus closes off to become the  median umbilical ligament ; however, if it does not seal close to the bladder, a blind pouch connected to the bladder remains. This is usually asymptomatic but can lead to recurrent  urinary tract infections . If the urachus is wholly patent,  urine  can drain from the bladder to an opening by the  umbilicus , a condition known as  urachal fistula . [ 1 ]


A  urachal fistula  is a  congenital disorder  caused by the persistence of the  allantois  (later,  urachus ), the structure that connects an embryo's  bladder  to the  yolk sac . Normally, the urachus closes off to become the  median umbilical ligament ; however, if it remains open,  urine  can drain from the bladder to an opening by the  umbilicus . [ 1 ]


This condition is a rare defect, mostly found in children, and is also known as an open or  patent urachus . [ 2 ] [ 3 ]


A  ureteral neoplasm  is a type of  tumor  that can be primary, or associated with a  metastasis  from another site. [ 1 ]


Treatment may involve removal of the  kidney  and  ureter , or just the ureter. [ 2 ]


Classification of cancers often is oriented around the embryological origin of the tissue. In some contexts, the primary division is at the border of kidney and ureter, and in other contexts, the primary division is between derivatives of the  metanephric blastema  and those of the  ureteric bud . Because of this, neoplasia of the ureters are sometimes grouped with tumors of the  renal pelvis . [ 3 ] [ 4 ]


This article about a  neoplasm  is a  stub . You can help Wikipedia by  expanding it .


The  ureteric plexus  is a  nerve plexus  covering and innervating the  ureter . The plexus can be graduated into three parts, as the ureter itself can be divided: In the upper part of the ureter, the plexus gets its  nerve fibers  mainly from the  renal plexus , but also from the  abdominal aortic plexus . In the intermediate part the plexus receives nervous input from the  superior hypogastric plexus  and in the lower part from the  inferior hypogastric plexus .


The plexus contains both  sympathetic  and  parasympathetic  fibers, where the sympathetic components come from T11 to L2 levels of the  spinal cord . Preganglionic   vagal  fibers (vagal fibers before passing through a ganglion) run through the  celiac plexus  and reach the ureteric plexus.


Ureteritis  is a medical condition of the  ureter  that involves  inflammation . [ 1 ] [ 2 ]  One form is known as "ureteritis cystica". [ 3 ]


Eosinophilic  ureteritis has been observed. [ 4 ]


Ureteritis is often considered part of a  urinary tract infection . [ citation needed ]


The  urethral crest  is an anatomical feature present in the  urinary system  of both males and females.


In males, the urethral crest is known as the  crista urethralis masculinae , or the  crista phallica , and is a longitudinal fold on the posterior wall of the  urethra  extending from the  uvula of the bladder  through the  prostatic urethra . [ 1 ]
It is from 15 to 17 mm. in length, and about 3 mm. in height, and contains muscular and erectile tissue.
When distended, it may serve to prevent the passage of the  semen  backward into the  bladder . [ 2 ]


In females, it is known as the  crista urethralis femininae , and is a conspicuous longitudinal fold of  mucosa  on the posterior wall of the urethra. [ 3 ]


Doctors have documented numerous cases of  insertion of  foreign bodies  into the  urethra , typically as the result of  auto-erotic  activities. This can result in infections and serious internal bleeding. [ 1 ] [ 2 ]


A wide variety of solid objects have been reported to have been inserted into the urethra, including batteries, safety pins, straws, [ 2 ]  and telephone wires. [ 3 ]  Liquefied objects have also been inserted into the urethra, such as an  injection of cocaine [ 4 ]  (which, arguably, had harmful results [ 5 ] [ clarification needed ] ).


The  Chuck Palahniuk  story "Guts", from the novel  Haunted , includes the story of a boy in his early teens inserting candle wax into his urethra. [ 6 ]


The  urethral or periurethral glands  (also  Littré glands  after  Alexis Littré ) [ 1 ]  are  glands  that branch off the wall of the  urethra  of mammals. The glands secrete  mucus [ 2 ]  and are most numerous in the section of the urethra that runs through the  penis . Urethral glands produce a  colloid  secretion containing  glycosaminoglycans ; this secretion protects the  epithelium  against  urine . [ 3 ]


Untreated  urethritis  can lead to infection of the urethral glands, which can in turn result in impeding  urethral strictures .


List of distinct cell types in the adult human body


Urine sodium  is a measurement of the concentration of  sodium  in the  urine .


It is a test ordered to distinguish between forms of renal failure and to classify the severity of hyponatremia. [ 1 ]


The urine sodium is expressed as a concentration (such as millimoles per liter).  The result must therefore be interpreted in the context of the degree of urine concentration present.  Alternatively, the urine sodium can be standardized to the excretion of  creatinine  using a formula such as the  fractional excretion of sodium (FENa) .


Because the  hypothalamus / osmoreceptor  system ordinarily works well to cause drinking or urination to restore the body's sodium concentrations to normal, this system can be used in medical treatment to regulate the body's total fluid content, by first controlling the body's sodium content. Thus, when a powerful  diuretic  drug is given which causes the kidneys to excrete sodium, the effect is accompanied by an excretion of body water (water loss accompanies sodium loss). This happens because the kidney is unable to efficiently retain water while excreting large amounts of sodium. In addition, after sodium excretion, the  osmoreceptor  system may sense lowered sodium concentration in the blood and then direct compensatory urinary water loss in order to correct the  hyponatremic  (low blood sodium) state.


Classifying renal disease


When classifying renal disease, urine sodium levels can provide insight into the underlying cause. [ 2 ]  A low urine sodium (<20 mEq/L) indicates an  acute kidney injury  (AKI), while sodium concentrations present high (>40 mEq/L) in  acute tubular necrosis . [ 2 ]


A  urogenital neoplasm  is a tumor of the  urogenital  system. [ 1 ]


Types include:


A urothelial papilloma is a rare, noncancerous tumor found within the urinary tract.


The most common presenting symptom is hematuria (blood in urine). The average age at which it occurs is 46 years old.


The tumor is made of a fibrovascular core covered by seemingly normal urothelium tissue. Under microscope, papillary (finger-like) fronds can be seen that feature occasional branching, but no fusion.


The tumors are diploid (contain two sets of chromosomes). They commonly show FGFR3 mutations. [ 1 ]


The  uterine cavity  is the inside of the  uterus . It is triangular in shape, the base (broadest part) being formed by the internal surface of the  body of the uterus  between the openings of the  fallopian tubes , the apex by the  internal orifice of the uterus  through which the cavity of the body communicates with the  canal of the cervix . The uterine cavity where it enters the openings of the fallopian tubes is a mere slit, flattened antero-posteriorly.


This article incorporates text in the  public domain  from  page 1260  of the 20th edition of   Gray's Anatomy   (1918)


The  uterine horns  ( cornua of uterus ) are the points in the upper  uterus  where the  fallopian tubes  or  oviducts  exit to meet the  ovaries . They are one of the points of attachment for the  round ligament of uterus  (the other being the  mons pubis ). They also provide attachment to the  ovarian ligament , which is located below the fallopian tube at the back, while the round ligament of uterus is located below the tube at the front.


The uterine horns are far more prominent in other animals (such as cows [ 1 ]  and cats [ 2 ] ) than they are in  humans . In the cat, implantation of the embryo occurs in one of the two uterine horns, not the body of the uterus itself.


Occasionally, if a fallopian tube does not connect, the uterine horn will fill with blood each month, and a minor one-day surgery will be performed to remove it.  Often, people who are born with this have trouble getting  pregnant  as both  ovaries  are functional and either may ovulate.  The spare  egg , that cannot travel the fallopian tube, is absorbed into the body.


Uterine hyperplasia , or  enlarged uterus , is a  medical symptom  in which the volume and size of the  uterus  in a female is abnormally high. It can be a symptom of  medical conditions  such as  adenomyosis ,  uterine fibroids ,  ovarian cysts , and  endometrial cancer . [ 1 ]


Uterine hypoplasia , also known as  naive uterus  or  infantile uterus , is a  reproductive disorder  characterized by  hypoplasia  of the  uterus . It is usually due to  pubertal failure / hypogonadism  and may be treated with  puberty induction  using  estrogens  and/or  progestogens .


The  uterine isthmus  is the inferior-posterior part of  uterus , on its  cervical  end — here, the uterine muscle ( myometrium ) is narrower and thinner. It connects the  body  and cervix. [ 1 ]


The uterine isthmus can become more compressibile in pregnancy, which is a finding known as  Hegar's sign .


The  fornices of the vagina  ( sg. :  fornix of the vagina  or  fornix vaginae ) are the  superior  portions of the  vagina , extending into the recesses created by the  vaginal portion of cervix . There is an anterior fornix and a posterior fornix. The word  fornix  is Latin for ' arch '.


During  sexual intercourse  in the  missionary position , the tip of the  penis  may reach the anterior fornix, while in the  rear-entry position  it may reach the posterior fornix. [ 1 ]


The anterior fornix is also called the  a-spot , an analogue to the  g-spot  (Gräfenberg spot), which is closer to the vaginal opening, and also on the anterior side of the vagina. [ 2 ]


This article incorporates text in the  public domain  from  page 1264  of the 20th edition of   Gray's Anatomy   (1918)


The  vaginal vault  is the expanded region of the vaginal canal at the internal end of the  vagina . [ 1 ]


The vaginal vault may  prolapse  after a  hysterectomy , as there is no uterus supporting the interior end of the vagina.


Colposacropexy  is often used for treating vaginal vault prolapse. A  Cochrane Collaboration  review [ needs update ]  found that limited data are available on optimal surgical approaches, including the use of  transvaginal surgical mesh  devices, in the form of a patch or  sling , similar to its implementation for abdominal  hernia . However, the use of a transvaginal mesh in treating vaginal prolapses is associated with side effects including  pain ,  infection , and  organ perforation . According to the  FDA , serious complications are "not rare." A number of  class action   lawsuits  have been filed and settled against several manufacturers of TVM devices.


Vasitis nodosa  is a  complication  experienced in approximately 66% of men who undergo  vasectomy . [ 1 ]  It is a  benign   nodular  thickening of the  vas deferens , in which small offshoots proliferate, infiltrating surrounding tissue. [ 2 ]   It can be mistaken for low-grade  adenocarcinoma  by  pathologists , [ 3 ]  and is implicated in late vasectomy failure. [ 2 ]


Vesicular appendages of the  epoöphoron  are small pedunculated vesicles of the  fimbriae  of the  uterine tube , or connected to the  broad ligament .  They were described by  Giovanni Battista Morgagni  and are remnants of the cranial part of the  mesonephric duct . Typically they are asymptomatic.


In the male, remnants of the paramesonephric duct may be present as well and are also known as  appendix of testis  or  hydatid of Morgagni .


They are rarely absent, and are attached either to the free margin of the mesosalpinx or
to one of the fimbriae, and are pedunculated vesicles, filled with fluid, about the size of a small pea.
The pedicles frequently attain a considerable length. [ 1 ]


Vestibular adenitis  is a condition affecting the  vagina . [ 1 ]  It is a chronic  inflammation  of the lesser  vestibular glands , which lie just outside the  hymenal ring . The condition can lead to small, extremely painful  ulcerations  of the  vestibular mucosa . [ 2 ]


Myiasis  is a parasitic infestation caused by larvae of several fly species. Diagnosis and treatment are generally quite simple. This infestation is, however, rarely seen in the  vulvar  area. Infestation of vulvar area with larvae and maggots is called  vulvar myiasis . Very few cases have been described in literature. [ 1 ]


Birth control , also known as  contraception ,  anticonception , and  fertility control , is the use of methods or devices to prevent  pregnancy . [ 1 ] [ 2 ]  Birth control has been used since ancient times, but effective and safe methods of birth control only became available in the 20th century. [ 3 ]  Planning, making available, and using human birth control is called  family planning . [ 4 ] [ 5 ]  Some cultures limit or discourage access to birth control because they consider it to be morally, religiously, or politically undesirable. [ 3 ]


The  World Health Organization  and  United States Centers for Disease Control and Prevention  provide guidance on the safety of birth control methods among women with specific medical conditions. [ 6 ] [ 7 ]  The most effective methods of birth control are  sterilization  by means of  vasectomy  in males and  tubal ligation  in females,  intrauterine devices  (IUDs), and  implantable birth control . [ 8 ]  This is followed by a number of  hormone-based methods  including  contraceptive pills ,  patches ,  vaginal rings , and  injections . [ 8 ]  Less effective methods include  physical barriers  such as  condoms ,  diaphragms  and  birth control sponges  and  fertility awareness methods . [ 8 ]  The least effective methods are  spermicides  and  withdrawal by the male before ejaculation . [ 8 ]  Sterilization, while highly effective, is not usually reversible; all other methods are reversible, most immediately upon stopping them. [ 8 ]   Safe sex  practices, such as with the use of condoms or  female condoms , can also help prevent  sexually transmitted infections . [ 9 ]  Other methods of birth control do not protect against sexually transmitted infections. [ 10 ]   Emergency birth control  can prevent pregnancy if taken within 72 to 120 hours after unprotected sex. [ 11 ] [ 12 ]  Some argue  not having sex  is also a form of birth control, but  abstinence-only sex education  may increase  teenage pregnancies  if offered without birth control education, due to non-compliance. [ 13 ] [ 14 ]


In  teenagers , pregnancies are at greater risk of poor outcomes. [ 15 ]  Comprehensive  sex education  and access to birth control decreases the rate of unintended pregnancies in this age group. [ 15 ] [ 16 ]  While all forms of birth control can generally be used by young people, [ 17 ]   long-acting reversible birth control  such as implants, IUDs, or vaginal rings are more successful in reducing rates of teenage pregnancy. [ 16 ]  After the delivery of a child, a woman who is not exclusively breastfeeding may become pregnant again after as few as four to six weeks. [ 17 ]  Some methods of birth control can be started immediately following the birth, while others require a delay of up to six months. [ 17 ]  In women who are breastfeeding,  progestin-only methods  are preferred over  combined oral birth control pills . [ 17 ]  In women who have reached  menopause , it is recommended that birth control be continued for one year after the last  menstrual period . [ 17 ]


About 222 million women who want to avoid pregnancy in  developing countries  are not using a modern birth control method. [ 18 ] [ 19 ]  Birth control use in developing countries has decreased the number of  deaths during or around the time of pregnancy  by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% if the full demand for birth control were met. [ 20 ] [ 21 ]  By lengthening the time between pregnancies, birth control can improve adult women's delivery outcomes and the survival of their children. [ 20 ]  In the developing world, women's earnings, assets, and weight, as well as their children's schooling and health, all improve with greater access to birth control. [ 22 ]  Birth control increases economic growth because of fewer dependent children, more women participating in the  workforce , and/or less use of scarce resources. [ 22 ] [ 23 ]


Birth control methods include  barrier methods ,  hormonal birth control ,  intrauterine devices  (IUDs),  sterilization , and behavioral methods. They are used before or during sex while  emergency contraceptives  are effective for up to five days after sex. Effectiveness is generally expressed as the percentage of women who become pregnant using a given method during the first year, [ 28 ]  and sometimes as a lifetime failure rate among methods with high effectiveness, such as  tubal ligation . [ 29 ]


Birth control methods fall into two main categories:  male contraception  and  female contraception . Common male contraceptives are  withdrawal ,  condoms , and  vasectomy . Female contraception is more developed compared to male contraception, these include  contraceptive pills  (combination and progestin-only pill), hormonal or non-hormonal  IUD ,  patch ,  vaginal ring ,  diaphragm ,  shot ,  implant ,  fertility awareness , and  tubal ligation .


The most effective methods are those that are long acting and do not require ongoing health care visits. [ 30 ]  Surgical sterilization, implantable hormones, and intrauterine devices all have first-year failure rates of less than 1%. [ 24 ]  Hormonal contraceptive pills, patches or vaginal rings, and the  lactational amenorrhea method  (LAM), if adhered to strictly, can also have first-year (or for LAM, first-6-month) failure rates of less than 1%. [ 30 ]  With typical use, first-year failure rates are considerably higher, at 9%, due to inconsistent use. [ 24 ]  Other methods such as condoms, diaphragms, and spermicides have higher first-year failure rates even with perfect usage. [ 30 ]  The  American Academy of Pediatrics  recommends  long acting reversible birth control  as first line for young individuals. [ 31 ]


While all methods of birth control have some potential adverse effects, the risk is less than that of pregnancy. [ 30 ]  After stopping or removing many methods of birth control, including oral contraceptives, IUDs, implants and injections, the rate of pregnancy during the subsequent year is the same as for those who used no birth control. [ 32 ]


For individuals with specific health problems, certain forms of birth control may require further investigations. [ 33 ]  For women who are otherwise healthy, many methods of birth control should not require a  medical exam —including birth control pills, injectable or implantable birth control, and condoms. [ 34 ]  For example, a  pelvic exam ,  breast exam , or blood test before starting birth control pills does not appear to affect outcomes. [ 35 ] [ 36 ] [ 37 ]  In 2009, the  World Health Organization  (WHO) published a detailed list of  medical eligibility criteria  for each type of birth control. [ 33 ]


Hormonal contraception  is available in a number of different forms, including  oral pills ,  implants  under the skin,  injections ,  patches ,  IUDs  and a  vaginal ring . They are currently available only for women, although hormonal contraceptives for men have been and are being clinically tested. [ 38 ]  There are two types of oral birth control pills, the  combined oral contraceptive pills  (which contain both  estrogen  and a  progestin ) and the  progestogen-only pills  (sometimes called minipills). [ 39 ]  If either is taken during pregnancy, they do not increase the risk of  miscarriage  nor cause  birth defects . [ 36 ]  Both types of birth control pills prevent  fertilization  mainly by inhibiting  ovulation  and thickening cervical mucus. [ 40 ] [ 41 ]  They may also change the lining of the uterus and thus decrease implantation. [ 41 ]  Their effectiveness depends on the user's adherence to taking the pills. [ 36 ]


Combined hormonal contraceptives are associated with a slightly increased risk of  venous  and  arterial blood clots . [ 42 ]  Venous clots, on average, increase from 2.8 to 9.8 per 10,000 women years [ 43 ]  which is still less than that associated with pregnancy. [ 42 ]  Due to this risk, they are not recommended in women over 35 years of age who continue to smoke. [ 44 ]  Due to the increased risk, they are included in decision tools such as the  DASH score  and  PERC rule  used to predict the risk of blood clots. [ 45 ]


The effect on sexual drive is varied, with increase or decrease in some but with no effect in most. [ 46 ]  Combined oral contraceptives reduce the risk of  ovarian cancer  and  endometrial cancer  and do not change the risk of breast cancer. [ 47 ] [ 48 ]  They often reduce menstrual bleeding and  painful menstruation cramps . [ 36 ]  The lower doses of estrogen released from the vaginal ring may reduce the risk of breast tenderness,  nausea , and headache associated with higher dose estrogen products. [ 47 ]


Progestin-only pills, injections and intrauterine devices are not associated with an increased risk of blood clots and may be used by women with a history of blood clots in their veins. [ 42 ] [ 49 ]  In those with a history of arterial blood clots, non-hormonal birth control or a progestin-only method other than the injectable version should be used. [ 42 ]  Progestin-only pills may improve menstrual symptoms and can be used by breastfeeding women as they do not affect  milk production . Irregular bleeding may occur with progestin-only methods, with some users reporting  no periods . [ 50 ]  The progestins  drospirenone  and  desogestrel  minimize the  androgenic  side effects but increase the risks of blood clots and are thus not first line. [ 51 ]  The perfect use first-year failure rate of  injectable progestin  is 0.2%; the typical use first failure rate is 6%. [ 24 ]


Barrier contraceptives  are devices that attempt to prevent pregnancy by physically preventing  sperm  from entering the  uterus . [ 52 ]  They include male  condoms ,  female condoms ,  cervical caps ,  diaphragms , and  contraceptive sponges  with  spermicide . [ 52 ]


Globally, condoms are the most common method of birth control. [ 53 ]   Male condoms  are put on a man's erect  penis  and physically block ejaculated sperm from entering the body of a sexual partner. [ 54 ]  Modern condoms are most often made from  latex , but some are made from other materials such as  polyurethane , or lamb's intestine. [ 54 ]   Female condoms  are also available, most often made of  nitrile , latex or polyurethane. [ 55 ]  Male condoms have the advantage of being inexpensive, easy to use, and have few adverse effects. [ 56 ]  Making condoms available to teenagers does not appear to affect the age of onset of sexual activity or its frequency. [ 57 ]  In Japan, about 80% of couples who are using birth control use condoms, while in Germany this number is about 25%, [ 58 ]  and in the United States it is 18%. [ 59 ]


Male condoms and the diaphragm with spermicide have typical use first-year failure rates of 18% and 12%, respectively. [ 24 ]  With perfect use condoms are more effective with a 2% first-year failure rate versus a 6% first-year rate with the diaphragm. [ 24 ]  Condoms have the additional benefit of helping to prevent the spread of some sexually transmitted infections such as  HIV/AIDS , however, condoms made from animal intestine do not. [ 8 ] [ 60 ]


Contraceptive sponges combine a barrier with a spermicide. [ 30 ]  Like diaphragms, they are inserted vaginally before intercourse and must be placed over the  cervix  to be effective. [ 30 ]  Typical failure rates during the first year depend on whether or not a woman has previously given birth, being 24% in those who have and 12% in those who have not. [ 24 ]  The sponge can be inserted up to 24 hours before intercourse and must be left in place for at least six hours afterward. [ 30 ]  Allergic reactions [ 61 ]  and more severe adverse effects such as  toxic shock syndrome  have been reported. [ 62 ]


The current  intrauterine devices  (IUD) are small devices, often T-shaped, containing either copper or  levonorgestrel , which are inserted into the uterus. They are one form of  long-acting reversible contraception  which are the most effective types of reversible birth control. [ 63 ]  Failure rates with the  copper IUD  is about 0.8% while the  levonorgestrel IUD  has a failure rates of 0.2% in the first year of use. [ 64 ]  Among types of birth control, they, along with birth control implants, result in the greatest satisfaction among users. [ 65 ]  As of 2007 [update] , IUDs are the most widely used form of reversible contraception, with more than 180 million users worldwide. [ 66 ]


Evidence supports effectiveness and safety in adolescents [ 65 ]  and those who have and have not previously had children. [ 67 ]  IUDs do not affect  breastfeeding  and can be inserted immediately after delivery. [ 68 ]  They may also be used immediately after an abortion. [ 69 ] [ 70 ]  Once removed, even after long term use, fertility returns to normal immediately. [ 71 ]


While  copper IUDs  may increase menstrual bleeding and result in more painful cramps, [ 72 ]   hormonal IUDs  may reduce menstrual bleeding or stop menstruation altogether. [ 68 ]  Cramping can be treated with painkillers like  non-steroidal anti-inflammatory drugs . [ 73 ]  Other potential complications include expulsion (2–5%) and rarely perforation of the uterus (less than 0.7%). [ 68 ] [ 73 ]  A previous model of the intrauterine device (the  Dalkon shield ) was associated with an increased risk of  pelvic inflammatory disease ; however, the risk is not affected with current models in those without  sexually transmitted infections  around the time of insertion. [ 74 ]  IUDs appear to decrease the risk of  ovarian cancer . [ 75 ]


Two broad categories exist, surgical and non-surgical.


Surgical sterilization  is available in the form of  tubal ligation  for women and  vasectomy  for men. [ 3 ]  Tubal ligation decreases the risk of  ovarian cancer . [ 3 ]  Short term complications are twenty times less likely from a vasectomy than a tubal ligation. [ 3 ] [ 76 ]  After a vasectomy, there may be swelling and pain of the scrotum which usually resolves in one or two weeks. [ 77 ]  Chronic scrotal pain associated with negative impact on quality of life occurs after vasectomy in about 1–2% of men. [ 78 ]  With tubal ligation, complications occur in 1 to 2 percent of procedures with serious complications usually due to the  anesthesia . [ 79 ]  Neither method offers protection from sexually transmitted infections. [ 3 ]  Sometimes,  salpingectomy  is also used for sterilization in women. [ 80 ]


Non-surgical sterilization  methods have also been explored.
Fahim [ 81 ] [ 82 ] [ 83 ]  et al. found that heat exposure, especially high-intensity ultrasound, was effective either for temporary or permanent contraception depending on the dose, e.g. selective destruction of germ cells and Sertoli cells without affecting Leydig cells or testosterone levels. Chemical, e.g. drug-based methods are also available, e.g. orally-administered Lonidamine [ 84 ]  for temporary, or permanent (depending on the dose) fertility management.
Boris [ 85 ]  provides a method for chemically inducing either temporary or non-reversible sterility, depending on the dose, "Permanent sterility in human males can be obtained by a single oral dosage containing from about 18 mg/kg to about 25 mg/kg".


The permanence of this decision may cause regret in some men and women. Of women who have undergone tubal ligation after the age of 30, about 6% regret their decision, as compared with 20–24% of women who received sterilization within one year of delivery and before turning 30, and 6% in  nulliparous  women sterilized before the age of 30. [ 86 ]  By contrast, less than 5% of men are likely to regret sterilization. Men who are more likely to regret sterilization are younger, have young or no children, or have an unstable marriage. [ 87 ]  In a survey of biological parents, 9% stated they would not have had children if they were able to do it over again. [ 88 ]


Although sterilization is considered a permanent procedure, [ 89 ]  it is possible to attempt a  tubal reversal  to reconnect the  fallopian tubes  or a  vasectomy reversal  to reconnect the  vasa deferentia . In women, the desire for a reversal is often associated with a change in spouse. [ 89 ]  Pregnancy success rates after tubal reversal are between 31 and 88 percent, with complications including an increased risk of  ectopic pregnancy . [ 89 ]  The number of males who request reversal is between 2 and 6 percent. [ 90 ]  Rates of success in fathering another child after reversal are between 38 and 84 percent; with success being lower the longer the time period between the vasectomy and the reversal. [ 90 ]   Sperm extraction  followed by  in vitro fertilization  may also be an option in men. [ 91 ]


Behavioral methods involve  regulating the timing  or method of intercourse to prevent introduction of sperm into the female reproductive tract, either altogether or when an egg may be present. [ 92 ]  If used perfectly the first-year failure rate may be around 3.4%; however, if used poorly first-year failure rates may approach 85%. [ 93 ]


Fertility awareness methods  involve determining the most fertile days of the  menstrual cycle  and avoiding unprotected intercourse. [ 92 ]  Techniques for determining fertility include monitoring  basal body temperature ,  cervical secretions , or the day of the cycle. [ 92 ]  They have typical first-year failure rates of 24%; perfect use first-year failure rates depend on which method is used and range from 0.4% to 5%. [ 24 ]  The evidence on which these estimates are based, however, is poor as the majority of people in trials stop their use early. [ 92 ]  Globally, they are used by about 3.6% of couples. [ 94 ]  If based on both basal body temperature and another primary sign, the method is referred to as symptothermal. First-year failure rates of 20% overall and 0.4% for perfect use have been reported in clinical studies of the symptothermal method. [ 95 ] [ 24 ]  A number of  fertility tracking  apps are available, as of 2016, but they are more commonly designed to assist those trying to get pregnant rather than prevent pregnancy. [ 96 ]


The  withdrawal method  (also known as coitus interruptus) is the practice of ending intercourse ("pulling out") before ejaculation. [ 97 ]  The main risk of the withdrawal method is that the man may not perform the maneuver correctly or in a timely manner. [ 97 ]  First-year failure rates vary from 4% with perfect usage to 22% with typical usage. [ 24 ]  It is not considered birth control by some medical professionals. [ 30 ]


There is little data regarding the sperm content of  pre-ejaculatory fluid . [ 98 ]  While some tentative research did not find sperm, [ 98 ]  one trial found sperm present in 10 out of 27 volunteers. [ 99 ]  The withdrawal method is used as birth control by about 3% of couples. [ 94 ]


Sexual abstinence  may be used as a form of birth control, meaning either not engaging in any type of sexual activity, or specifically not engaging in vaginal intercourse, while engaging in other forms of non-vaginal sex. [ 100 ] [ 101 ]  Complete sexual abstinence is 100% effective in preventing pregnancy. [ 102 ] [ 103 ]  However, among those who take a  pledge to abstain  from  premarital sex , as many as 88% who engage in sex, do so prior to marriage. [ 104 ]  The choice to abstain from sex cannot protect against pregnancy as a result of rape, and public health efforts emphasizing abstinence to reduce unwanted pregnancy may have limited effectiveness, especially in  developing countries  and among  disadvantaged groups . [ 105 ] [ 106 ]


Deliberate  non-penetrative sex  without vaginal sex or deliberate  oral sex  without vaginal sex are also sometimes considered birth control. [ 100 ]  While this generally avoids pregnancy, pregnancy can still occur with  intercrural sex  and other forms of penis-near-vagina sex (genital rubbing, and the penis exiting from  anal intercourse ) where sperm can be deposited near the entrance to the vagina and can travel along the vagina's lubricating fluids. [ 107 ] [ 108 ]


Abstinence-only sex education  does not reduce  teenage pregnancy . [ 10 ] [ 109 ]  Teen pregnancy rates and STI rates are generally the same or higher in states where students are given abstinence-only education, as compared with  comprehensive sex education . [ 109 ]  Some authorities recommend that those using abstinence as a primary method have backup methods available (such as condoms or emergency contraceptive pills). [ 110 ]


The  lactational amenorrhea method  involves the use of a woman's natural  postpartum infertility  which occurs after delivery and may be extended by  breastfeeding . [ 111 ]  For a postpartum woman to be infertile (protected from pregnancy), their periods have usually not yet returned (not menstruating), they are exclusively breastfeeding the infant, and the baby is younger than six months. [ 27 ]  If breastfeeding is the infant's only source of nutrition and the baby is less than 6 months old, 93–99% of women are estimated to have protection from becoming pregnant in the first six months (0.75–7.5% failure rate). [ 112 ] [ 113 ]  The failure rate increases to 4–7% at one year and 13% at two years. [ 114 ]  Feeding formula, pumping instead of nursing, the use of a  pacifier , and feeding solids all increase the chances of becoming pregnant while breastfeeding. [ 115 ]  In those who are exclusively breastfeeding, about 10% begin having periods before three months and 20% before six months. [ 114 ]  In those who are not breastfeeding, fertility may return as early as four weeks after delivery. [ 114 ]


Emergency contraceptive  methods are medications (sometimes misleadingly referred to as "morning-after pills") [ 116 ]  or devices used after unprotected sexual intercourse with the hope of preventing pregnancy. Emergency contraceptives are often given to victims of rape. [ 11 ]  They work primarily by preventing ovulation or fertilization. [ 3 ] [ 117 ]  They are unlikely to affect implantation, but this has not been completely excluded. [ 117 ]  A number of options exist, including  high dose birth control pills ,  levonorgestrel ,  mifepristone ,  ulipristal  and IUDs. [ 118 ]  All methods have minimal side effects. [ 118 ]  Providing emergency contraceptive pills to women in advance of sexual activity does not affect rates of sexually transmitted infections, condom use, pregnancy rates, or sexual risk-taking behavior. [ 119 ] [ 120 ]  In a UK study, when a three-month "bridge" supply of the  progestogen-only pill  was provided by a pharmacist along with emergency contraception after sexual activity, this intervention was shown to increase the likelihood that the person would begin to use an effective method of long-term contraception. [ 121 ] [ 122 ]


Levonorgestrel  pills, when used within 3 days, decrease the chance of pregnancy after a single episode of unprotected sex or condom failure by 70% (resulting in a pregnancy rate of 2.2%). [ 11 ]   Ulipristal , when used within 5 days, decreases the chance of pregnancy by about 85% (pregnancy rate 1.4%) and is more effective than levonorgestrel. [ 11 ] [ 118 ] [ 123 ]   Mifepristone  is also more effective than levonorgestrel, while copper IUDs are the most effective method. [ 118 ]  IUDs can be inserted up to five days after intercourse and prevent about 99% of pregnancies after an episode of unprotected sex (pregnancy rate of 0.1 to 0.2%). [ 3 ] [ 124 ]  This makes them the most effective form of emergency contraceptive. [ 125 ]  In those who are  overweight  or  obese , levonorgestrel is less effective and an IUD or ulipristal is recommended. [ 126 ]


Dual protection is the use of methods that prevent both  sexually transmitted infections  and pregnancy. [ 127 ]  This can be with condoms either alone or along with another birth control method or by the avoidance of  penetrative sex . [ 128 ] [ 129 ]


If pregnancy is a high concern, using two methods at the same time is reasonable. [ 128 ]  For example, two forms of birth control are recommended in those taking the anti- acne  drug  isotretinoin  or  anti-epileptic drugs  like  carbamazepine , due to the high risk of  birth defects  if taken during pregnancy. [ 130 ] [ 131 ]


Contraceptive use in  developing countries  is estimated to have decreased the number of  maternal deaths  by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% of deaths if the full demand for birth control were met. [ 20 ] [ 21 ]  These benefits are achieved by reducing the number of unplanned pregnancies that subsequently result in unsafe abortions and by preventing pregnancies in those at high risk. [ 20 ]


Birth control also improves child survival in the developing world by lengthening the time between pregnancies. [ 20 ]  In this population, outcomes are worse when a mother gets pregnant within eighteen months of a previous delivery. [ 20 ] [ 133 ]  Delaying another pregnancy after a  miscarriage , however, does not appear to alter risk and women are advised to attempt pregnancy in this situation whenever they are ready. [ 133 ]


Teenage pregnancies , especially among younger teens, are at greater risk of adverse outcomes including  early birth ,  low birth weight , and  death of the infant . [ 15 ]  In 2012 in the United States 82% of pregnancies in those between the ages of 15 and 19 years old are unplanned. [ 73 ]  Comprehensive  sex education  and access to birth control are effective in decreasing pregnancy rates in this age group. [ 134 ]


Birth control methods, especially  hormonal methods , can also have undesirable side effects. Intensity of side effects can range from minor to debilitating, and varies with individual experiences. These most commonly include change in menstruation regularity and flow, nausea, breast tenderness, headaches, weight gain, and mood changes (specifically an increase in depression and anxiety). [ 135 ] [ 136 ]  Additionally, hormonal contraception can contribute to bone mineral density loss, impaired glucose metabolism, increased risk of venous thromboembolism. [ 136 ] [ 135 ]  Comprehensive sex education and transparent discussion of birth control side effects and contraindications between healthcare provider and patient is imperative. [ 135 ]


In the developing world, birth control increases economic growth due to there being fewer dependent children and thus more women participating in or increased contribution to the  workforce  – as they are usually the primary  caregiver  for children. [ 22 ]  Women's earnings, assets,  body mass index , and their children's schooling and body mass index all improve with greater access to birth control. [ 22 ]   Family planning , via the use of modern birth control, is one of the most  cost-effective  health interventions. [ 137 ]  For every dollar spent, the United Nations estimates that two to six dollars are saved. [ 19 ]  These cost savings are related to preventing unplanned pregnancies and decreasing the spread of sexually transmitted illnesses. [ 137 ]  While all methods are beneficial financially, the use of copper IUDs resulted in the greatest savings. [ 137 ]


The total medical cost for a pregnancy, delivery and care of a newborn in the United States is on average $21,000 for a vaginal delivery and $31,000 for a  caesarean delivery  as of 2012. [ 138 ]  In most other countries, the cost is less than half. [ 138 ]  For a child born in 2011, an average US family will spend $235,000 over 17 years to raise them. [ 139 ]


Globally, as of 2009, approximately 60% of those who are married and able to have children use birth control. [ 141 ]  How frequently different methods are used varies widely between countries. [ 141 ]  The most common method in the developed world is condoms and oral contraceptives, while in Africa it is oral contraceptives and in Latin America and Asia it is sterilization. [ 141 ]  In the developing world overall, 35% of birth control is via female sterilization, 30% is via IUDs, 12% is via oral contraceptives, 11% is via condoms, and 4% is via male sterilization. [ 141 ]


While less used in the developed countries than the developing world, the number of women using IUDs as of 2007 was more than 180 million. [ 66 ]  Avoiding sex when fertile is used by about 3.6% of women of childbearing age, with usage as high as 20% in areas of South America. [ 142 ]  As of 2005, 12% of couples are using a male form of birth control (either condoms or a vasectomy) with higher rates in the developed world. [ 143 ]  Usage of male forms of birth control has decreased between 1985 and 2009. [ 141 ]  Contraceptive use among women in  Sub-Saharan Africa  has risen from about 5% in 1991 to about 30% in 2006. [ 144 ]


As of 2012, 57% of women of childbearing age want to avoid pregnancy (867 of 1,520 million). [ 145 ]  About 222 million women, however, were not able to access birth control, 53 million of whom were in sub-Saharan Africa and 97 million of whom were in Asia. [ 145 ]  This results in 54 million unplanned pregnancies and nearly 80,000 maternal deaths a year. [ 141 ]  Part of the reason that many women are without birth control is that many countries limit access due to religious or political reasons, [ 3 ]  while another contributor is poverty. [ 146 ]  Due to restrictive abortion laws in Sub-Saharan Africa, many women turn to unlicensed abortion providers for  unintended pregnancy , resulting in about 2–4% obtaining  unsafe abortions  each year. [ 146 ]


The Egyptian  Ebers Papyrus  from 1550 BC and the  Kahun Papyrus  from 1850 BC have within them some of the earliest documented descriptions of birth control: the use of honey,  acacia  leaves and lint to be placed in the vagina to block sperm. [ 147 ] [ 148 ]   Silphium , a species of  giant fennel  native to north Africa, may have been used as birth control in  ancient Greece  and the  ancient Near East . [ 149 ] [ 150 ]  Due to its desirability, by the first century AD, it had become so rare that it was worth more than its weight in silver and, by late antiquity, it was fully extinct. [ 149 ]  Most methods of birth control used in antiquity were probably ineffective. [ 151 ]


The  ancient Greek  philosopher  Aristotle  ( c.  384–322 BC) recommended applying  cedar oil  to the womb before intercourse, a method which was probably only effective on occasion. [ 151 ]  A  Hippocratic  text  On the Nature of Women  recommended that a woman drink a copper  salt  dissolved in water, which it claimed would prevent pregnancy for a year. [ 151 ]  This method was not only ineffective, but also dangerous, as the later medical writer  Soranus of Ephesus  ( c.  98–138 AD) pointed out. [ 151 ]  Soranus attempted to list reliable methods of birth control based on rational principles. [ 151 ]  He rejected the use of superstition and amulets and instead prescribed mechanical methods such as vaginal plugs and pessaries using wool as a base covered in oils or other gummy substances. [ 151 ]  Many of Soranus's methods were probably also ineffective. [ 151 ]


In medieval Europe, any effort to halt pregnancy was deemed immoral by the  Catholic Church , [ 147 ]  although it is believed that women of the time still used a number of birth control measures, such as  coitus interruptus  and inserting  lily  root and  rue  into the vagina. [ 152 ]  Women in the Middle Ages were also encouraged to tie weasel testicles around their thighs during sex to prevent pregnancy. [ 153 ]  The oldest condoms discovered to date were recovered in the ruins of  Dudley Castle  in England, and are dated back to 1640. [ 153 ]  They were made of animal gut, and were most likely used to prevent the spread of sexually transmitted infections during the  English Civil War . [ 153 ]   Casanova , living in 18th-century Italy, described the use of a lambskin covering to prevent pregnancy; however, condoms only became widely available in the 20th century. [ 147 ]


The birth control movement developed during the 19th and early 20th centuries. [ 154 ]  The  Malthusian League , based on the ideas of  Thomas Malthus , was established in 1877 in the United Kingdom to educate the public about the importance of  family planning  and to advocate for getting rid of penalties for promoting birth control. [ 155 ]  It was founded during the "Knowlton trial" of  Annie Besant  and  Charles Bradlaugh , who were prosecuted for publishing on various methods of birth control. [ 156 ]


In the United States,  Margaret Sanger  and Otto Bobsein popularized the phrase "birth control" in 1914. [ 157 ] [ 158 ]  Sanger primarily advocated for birth control on the idea that it would prevent women from seeking unsafe abortions, but during her lifetime, she began to campaign for it on the grounds that it would reduce mental and physical defects. [ 159 ] [ 160 ]  She was mainly active in the United States but had gained an international reputation by the 1930s. At the time, under the  Comstock Law , distribution of birth control information was illegal. She  jumped bail  in 1914 after her arrest for distributing birth control information and left the United States for the United Kingdom. [ 161 ]  In the U.K., Sanger, influenced by Havelock Ellis, further developed her arguments for birth control. She believed women needed to enjoy sex without fearing a pregnancy. During her time abroad, Sanger also saw a more flexible  diaphragm  in a Dutch clinic, which she thought was a better form of contraceptive. [ 160 ]  Once Sanger returned to the United States, she established a short-lived birth-control clinic with the help of her sister, Ethel Bryne, based in the Brownville section of  Brooklyn , New York [ 162 ]  in 1916. It was shut down after eleven days and resulted in her arrest. [ 163 ]  The publicity surrounding the arrest, trial, and appeal sparked birth control activism across the United States. [ 164 ]  Besides her sister, Sanger was helped in the movement by her first husband, William Sanger, who distributed copies of "Family Limitation." Sanger's second husband, James Noah H. Slee, would also later become involved in the movement, acting as its main funder. [ 160 ]  Sanger also contributed to the funding of research into hormonal contraceptives in the 1950s. [ 165 ]  She helped fund research John Rock, and biologist Gregory Pincus that resulted in the first hormonal contraceptive pill, later called Enovid. [ 166 ]  The first human trials of the pill were done on patients in the Worcester State Psychiatric Hospital, after which  clinical testing was done in Puerto Rico  before Enovid was approved for use in the U.S.. The people participating in these trials were not fully informed on the medical implications of the pill, and often had minimal to no other family planning options. [ 167 ] [ 168 ]  The newly approved birth control method was not made available to the participants after the trials, and contraceptives are still not widely accessible in Puerto Rico. [ 166 ]


The increased use of birth control was seen by some as a form of social decay. [ 169 ]  A decrease of fertility was seen as a negative. Throughout the Progressive Era (1890–1920), there was an increase of voluntary associations aiding the contraceptive movement. [ 169 ]  These organizations failed to enlist more than 100,000 women because the use of birth control was often compared to eugenics; [ 169 ]  however, there were women seeking a community with like-minded women. The ideology that surrounded birth control started to gain traction during the Progressive Era due to voluntary associations establishing community. Birth control was unlike the Victorian Era because women wanted to manage their sexuality. The use of birth control was another form of self-interest women clung to. This was seen as women began to gravitate towards strong figures, like the  Gibson Girl . [ 170 ]


The first permanent birth-control clinic was established in Britain in 1921 by  Marie Stopes  working with the Malthusian League. [ 171 ]  The clinic, run by midwives and supported by visiting doctors, [ 172 ]  offered women's birth-control advice and taught them the use of a  cervical cap . Her clinic made contraception acceptable during the 1920s by presenting it in scientific terms. In 1921, Sanger founded the American Birth Control League, which later became the  Planned Parenthood  Federation of America. [ 173 ]  In 1924 the Society for the Provision of Birth Control Clinics was founded to campaign for municipal clinics; this led to the opening of a second clinic in  Greengate, Salford  in 1926. [ 174 ]  Throughout the 1920s, Stopes and other  feminist  pioneers, including  Dora Russell  and  Stella Browne , played a major role in breaking down  taboos  about sex. In April 1930 the Birth Control Conference assembled 700 delegates and was successful in bringing birth control and abortion into the political sphere – three months later, the  Ministry of Health , in the United Kingdom, allowed local authorities to give birth-control advice in welfare centres. [ 175 ]


The National Birth Control Association was founded in Britain in 1931, and became the  Family Planning Association  eight years later. The Association amalgamated several British birth control-focused groups into 'a central organisation' for administering and overseeing birth control in Britain. The group incorporated the Birth Control Investigation Committee, a collective of physicians and scientists that was founded to investigate scientific and medical aspects of contraception with 'neutrality and impartiality'. [ 176 ]  Subsequently, the Association effected a series of  'pure'  and  'applied'  product and safety standards that manufacturers must meet to ensure their contraceptives could be prescribed as part of the Association's standard two-part-technique combining 'a rubber appliance to protect the mouth of the womb' with a 'chemical preparation capable of destroying... sperm'. [ 177 ]  Between 1931 and 1959, the Association founded and funded a series of tests to assess chemical efficacy and safety and rubber quality. [ 178 ]  These tests became the basis for the Association's Approved List of contraceptives, which was launched in 1937, and went on to become an annual publication that the expanding network of FPA clinics relied upon as a means to 'establish facts [about contraceptives] and to publish these facts as a basis on which a sound public and scientific opinion can be built'. [ 179 ]


In 1936, the  United States Court of Appeals for the Second Circuit  ruled in  United States v. One Package of Japanese Pessaries  that medically prescribing contraception to save a person's life or well-being was not illegal under the  Comstock Laws . Following this decision, the  American Medical Association  Committee on Contraception revoked its 1936 statement condemning birth control. [ 180 ]  A national survey in 1937 showed 71 percent of the adult population supported the use of contraception. [ 181 ]  By 1938, 374 birth control clinics were running in the United States despite their advertisement still being illegal. [ 182 ]   First Lady   Eleanor Roosevelt  publicly supported birth control and family planning. [ 183 ]  The restrictions on birth control in the Comstock laws were effectively rendered null and void by  Supreme Court  decisions  Griswold v. Connecticut  (1965) [ 184 ]  and  Eisenstadt v. Baird  (1972). [ 185 ]  In 1966,  President Lyndon B. Johnson  started endorsing public funding for family planning services, and the Federal Government began subsidizing birth control services for low-income families. [ 186 ]   The Affordable Care Act , passed into law on March 23, 2010, under President  Barack Obama , requires all plans in the Health Insurance Marketplace to cover contraceptive methods. These include barrier methods, hormonal methods, implanted devices, emergency contraceptives, and sterilization procedures. [ 187 ]


In 1909, Richard Richter developed the first intrauterine device made from silkworm gut, which was further developed and marketed in Germany by  Ernst Gräfenberg  in the late 1920s. [ 188 ]  In 1951, an Austrian-born American chemist, named  Carl Djerassi  at  Syntex  in Mexico City made the hormones in progesterone pills using Mexican yams ( Dioscorea mexicana ). [ 189 ]  Djerassi had chemically created the pill but was not equipped to distribute it to patients. Meanwhile,  Gregory Pincus  and  John Rock  with help from the  Planned Parenthood Federation of America  developed the first birth control pills in the 1950s, such as  mestranol/noretynodrel , which became publicly available in the 1960s through the Food and Drug Administration under the name  Enovid . [ 173 ] [ 190 ]   Medical abortion  became an alternative to surgical abortion with the availability of  prostaglandin analogs  in the 1970s and  mifepristone  in the 1980s. [ 191 ]


Human rights agreements require most governments to provide family planning and contraceptive information and services. These include the requirement to create a national plan for family planning services, remove laws that limit access to family planning, ensure that a wide variety of safe and effective birth control methods are available including emergency contraceptives, make sure there are appropriately trained healthcare providers and facilities at an affordable price, and create a process to review the programs implemented. If governments fail to do the above it may put them in breach of binding international treaty obligations. [ 192 ]


In the United States, the 1965 Supreme Court decision  Griswold v. Connecticut  overturned a state law prohibiting dissemination of contraception information based on a constitutional right to privacy for marital relationships. In 1972,  Eisenstadt v. Baird  extended this right to privacy to single people. [ 193 ]


In 2010, the United Nations launched the  Every Woman Every Child  movement to assess the progress toward meeting women's contraceptive needs. The initiative has set a goal of increasing the number of users of modern birth control by 120 million women in the world's 69 poorest countries by 2020. Additionally, they aim to eradicate discrimination against girls and young women who seek contraceptives. [ 194 ]  The  American Congress of Obstetricians and Gynecologists  (ACOG) recommended in 2014 that oral birth control pills should be  over the counter medications . [ 195 ]


Since at least the 1870s, American religious, medical, legislative, and legal commentators have debated contraception laws. Ana Garner and Angela Michel have found that in these discussions men often attach reproductive rights to moral and political matters, as part of an ongoing attempt to regulate human bodies. In press coverage between 1873 and 2013 they found a divide between institutional ideology and real-life experiences of women. [ 196 ]


Religions vary widely in their views of the ethics of birth control. [ 197 ]  The  Roman Catholic Church  re-affirmed its teachings in  1968  that only  natural family planning  is permissible, [ 198 ]  although large numbers of Catholics in  developed countries  accept and use modern methods of birth control. [ 199 ] [ 200 ] [ 201 ]  The  Greek Orthodox Church  admits a possible exception to its traditional teaching forbidding the use of artificial contraception, if used within marriage for certain purposes, including the spacing of births. [ 202 ]  Among  Protestants , there is a wide range of views from supporting none, such as in the  Quiverfull movement , to allowing all methods of birth control. [ 203 ]  Views in Judaism range from the stricter  Orthodox  sect, which prohibits all methods of birth control, to the more relaxed  Reform  sect, which allows most. [ 204 ]   Hindus  may use both natural and modern contraceptives. [ 205 ]  A common  Buddhist  view is that preventing conception is acceptable, while intervening after conception has occurred is not. [ 206 ]  In  Islam , contraceptives are allowed if they do not threaten health, although their use is discouraged by some. [ 207 ]


September 26 is World Contraception Day, devoted to raising awareness and improving education about sexual and reproductive health, with a vision of  a world where every pregnancy is wanted. [ 208 ]  It is supported by a group of governments and international NGOs, including the  Office of Population Affairs , the Asian Pacific Council on Contraception, Centro Latinamericano Salud y Mujer, the European Society of Contraception and Reproductive Health, the  German Foundation for World Population , the International Federation of Pediatric and Adolescent Gynecology,  International Planned Parenthood Federation , the  Marie Stopes International ,  Population Services International , the  Population Council , the  United States Agency for International Development  (USAID), and  Women Deliver . [ 208 ]


There are a number of  common misconceptions  regarding sex and pregnancy. [ 209 ]   Douching  after sexual intercourse is not an effective form of birth control. [ 210 ]  Additionally, it is associated with a number of health problems and thus is not recommended. [ 211 ]  Women can become pregnant the first time they have sexual intercourse [ 212 ]  and in any  sexual position . [ 213 ]  It is possible, although not very likely, to become pregnant during menstruation. [ 214 ]  Contraceptive use, regardless of its duration and type, does not have a negative effect on the ability of women to conceive following termination of use and does not significantly delay fertility. Women who use oral contraceptives for a longer duration may have a slightly lower rate of pregnancy than do women using oral contraceptives for a shorter period of time, possibly due to fertility decreasing with age. [ 215 ]


Access to birth control may be affected by finances and the laws within a region or country. [ 216 ]  In the United States African American, Hispanic, and young women are disproportionately affected by limited access to birth control, as a result of financial disparity. [ 217 ] [ 218 ]  For example, Hispanic and African American women often lack insurance coverage and are more often poor. [ 219 ]  New immigrants in the United States are not offered preventive care such as birth control. [ 220 ]


In the United Kingdom contraception can be obtained free of charge via contraception clinics,  sexual health  or GUM ( genitourinary medicine ) clinics, via some GP surgeries, some young people's services and pharmacies. [ 221 ] [ 222 ]


In September 2021, France announced that women aged under 25 in France will be offered free contraception from 2022. It was elaborated that they "would not be charged for medical appointments, tests, or other medical procedures related to birth control" and that this would "cover hormonal contraception, biological tests that go with it, the prescription of contraception and all care related to this contraception". [ 223 ]


From August 2022 onwards contraception for women aged between 17 and 25 years will be free in the  Republic of Ireland . [ 224 ] [ 225 ]


In most parts of the world, the political attitude to contraception determines whether and how much state provisioning of contraceptive care occurs. In the United States, for example, the Republican party and the Democratic party have held opposite positions, contributing to continuous policy shifts over the years. [ 226 ] [ 227 ]  In the 2010s, policies, and attitudes to contraceptive care shifted abruptly between Obama's and Trump's administrations. [ 226 ]  The Trump administration extensively overturned the efforts for contraceptive care, and reduced federal spending, compared to efforts and funding during the Obama administration. [ 226 ]


Free the Pill , a collaboration between  Advocates for Youth  and  Ibis Reproductive Health  are working to bring birth control over-the-counter, covered by insurance with no age-restriction throughout the United States. [ 228 ] [ 229 ] [ 230 ]


On July 13, 2023, the first US daily oral nonprescription over-the-counter birth control pill was approved for manufacturer by the  FDA . The pill, Opill is expected to be more effective in preventing unintended pregnancies than condoms are. Opill is expected to be available in 2024 but the price has yet to be set.  Perrigo , a pharmaceutical company based in Dublin is the manufacturer. [ 231 ]


Improvements of existing birth control methods are needed, as around half of those who get pregnant unintentionally are using birth control at the time. [ 30 ]  A number of alterations of existing contraceptive methods are being studied, including a better female condom, an improved  diaphragm , a patch containing only progestin, and a vaginal ring containing long-acting progesterone. [ 232 ]  This vaginal ring appears to be effective for three or four months and is currently available in some areas of the world. [ 232 ]  For women who rarely have sex, the taking of the hormonal birth control  levonorgestrel  around the time of sex looks promising. [ 233 ]


A number of methods to perform sterilization via the cervix are being studied. One involves putting  quinacrine  in the uterus which causes scarring and infertility. While the procedure is inexpensive and does not require surgical skills, there are concerns regarding long-term side effects. [ 234 ]  Another substance,  polidocanol , which functions in the same manner is being looked at. [ 232 ]  A device called  Essure , which expands when placed in the fallopian tubes and blocks them, was approved in the United States in 2002. [ 234 ]  In 2016, a  black boxed warning  regarding potentially serious side effects was added, [ 235 ] [ 236 ]  and in 2018, the device was discontinued. [ 237 ]


Despite high levels of interest in male contraception, [ 238 ] [ 239 ] [ 240 ]  progress been stymied by a lack of industry involvement. Most funding for male contraceptive research is derived from government or philanthropic sources. [ 241 ] [ 242 ] [ 243 ] [ 244 ]


A number of novel contraceptive methods based on hormonal and non-hormonal mechanisms of action are in various stages of  research and development , up to and including  clinical trials , [ 245 ] [ 246 ] [ 247 ] [ 248 ] [ 249 ] [ 250 ]  including gels, pills, injectables, implants, wearables, and oral contraceptives. [ 251 ] [ 252 ] [ 253 ]


Recent avenues of research include  proteins  and  genes  required for male  fertility . For instance, the  serine/threonine-protein kinase  33 (STK33) is a  testis -enriched  kinase  that is indispensable for male fertility in humans and mice. An inhibitor of this kinase,  CDD-2807 , has recently been identified and induced reversible male  infertility  without measurable  toxicity  in mice. [ 254 ]  Such an inhibitor would be a potent male contraceptive if it passed safety and efficacy tests.


Neutering  or spaying, which involves removing some of the reproductive organs, is often carried out as a method of birth control in household pets. Many  animal shelters  require these procedures as part of adoption agreements. [ 255 ]  In large animals the surgery is known as  castration . [ 256 ]


Birth control is also being considered as an alternative to hunting as a means of controlling  overpopulation in wild animals . [ 257 ]   Contraceptive vaccines  have been found to be effective in a number of different animal populations. [ 258 ] [ 259 ]  Kenyan goat herders fix a skirt, called an  olor , to male goats to prevent them from impregnating female goats. [ 260 ]


Bedsider.org (Bedsider)  is a free  birth control  support network for women ages 18–29. The network is operated by  The National Campaign to Prevent Teen and Unplanned Pregnancy ; a research based non-profit, non-partisan organization located in Washington, D.C. Launched in November 2011, its goal is to help women find the method of  birth control  that’s right for them and learn how to use it consistently and effectively. [ 1 ]   The campaign is developed in partnership with  IDEO , [ 2 ]  a global innovation and design firm and  Carbon Five , a development firm in San Francisco.


Bedsider provides users with tools to explore and  compare all available methods of contraception , to set up birth control or appointment reminders, and to view videos of young men and women’s personal experiences with various methods of contraception. Bedsider also offers a weekly column on sex, love, and life as well as a series of animated shorts that debunk myths about birth control. In addition, Bedsider provides the latest news on contraception and allows website visitors to type in their zip code to find the closest locations that provide contraception over the counter.  Bedsider is also mobile and can be used on an  iPhone  or an  Android  device.


On November 10, 2011, the  Ad Council  launched a major marketing campaign in support of the Bedsider program. The ads and PSAs created by the ad council address pressing social issues through multiple media outlets. These ads can be found on Bedsider.org, but will also be used on television and in newspapers and other publications in order to further promote Bedsider as a tool for young women around the country. [ 3 ]


Bedsider has received awards for its design and layout, [ 4 ]  and acceptance by media outlets such as the  Associated Press [ 5 ]  and  CNN . Additionally, Bedsider has also garnered the support of many medical and public health groups. [ 6 ]  All medical content found on Bedsider was developed with the assistance of many experts who are a part of The National Campaign to Prevent Teen and Unplanned Pregnancy’s Medical Advisory Committee.


Controversy over the beginning of pregnancy occurs in different contexts, particularly as it is discussed within the debate of  abortion in the United States .  Because an  abortion  is defined as ending an established pregnancy, rather than as destroying a fertilized egg, depending on when pregnancy is considered to begin, some methods of  birth control  as well as some methods of  infertility treatment  might be classified as  causing abortions .


The controversy is not primarily a scientific issue, since knowledge of human reproduction and development has become very refined; the linguistic questions remain debated for other reasons. The issue poses larger social, legal, medical, religious, philosophical, and political ramifications because some people, such as  Concerned Women for America , identify the beginning of a pregnancy as the beginning of an individual human being's life. [ 1 ]   Many of these arguments are related to the  anti-abortion movement .  In this way of thinking, if the pregnancy has not yet begun, then stopping the process is not  abortion  and therefore can contain none of the moral issues associated with abortion, but if it is a pregnancy, then stopping it is a morally significant act.


A major complication is that ideological and religious concepts such as " ensoulment " (whether or not a human being is said to have gone from mere matter to having a spiritual entity inside) and " personhood " (whether or not a human being is said to be a distinct individual with innate  human rights  versus otherwise) exist outside of  scientific analysis , and thus many individuals have argued that the beginning of pregnancy cannot be determined strictly through physical evidence alone. No experiment exists (or can exist) to measure the  spirituality  of an object or living thing in the same way that height, temperature, weight, etc. can be studied.


Generally speaking, some ideological and religious commentaries have argued that pregnancy should be stated as beginning at the first, exact moment of conception in which a  human sperm  makes full contact with an  egg cell .  In contrast, other commentaries have argued that the  duration of pregnancy  begins at some other point, such as when the  fertilization process  ends (when a new, independent cell genetically distinct from the prior egg and sperm exists) or when  implantation occurs  (when the new set of cells lodges itself against the uterine wall, allowing it to grow rapidly). The ambiguity's implications mean that, despite the scientific community being able to describe the physical processes in detail, the decision about what should be called " abortion " and what should be called " contraception " or pregnancy prevention are not agreed upon. [ 1 ]


Traditionally, doctors have measured  pregnancy  from a number of convenient points, including the day of last  menstruation ,  ovulation ,  fertilization ,  implantation  and chemical detection. [ 2 ]  This has led to some confusion about the precise length of human pregnancy, as each measuring point yields a different figure.


At its 2004 Annual Meeting, The  American Medical Association  passed a resolution in favor of making "Plan B"  emergency contraception  available over-the-counter, and one of the claims in the resolution was that  hormonal contraception  that may affect implantation "cannot terminate an established pregnancy." [ 5 ]  Similarly, the  British Medical Association  has defined an "established pregnancy" as beginning at implantation. [ 6 ]  The legal definition in the United Kingdom is not clear. [ 7 ]


Other definitions exist. The American Heritage Stedman's  Medical Dictionary  defines "pregnancy" as "from conception until birth." [ 8 ]   Definitions like this may add to a lay person's confusion, as "conception" in a scientific context may be defined as fertilization, [ 9 ] [ 10 ]  in a medical context can mean either fertilization [ 11 ] [ 12 ]   or implantation [ 13 ]  but in lay terms may mean both. [ 14 ]


Whether conception refers to fertilization or implantation would seemingly even impact "established pregnancies" such as an  ectopic pregnancy . If conception is defined as at implantation, ectopic pregnancies could not be called pregnancies. However, some medical professionals who oppose birth control, [ 15 ]  such as Walter Larimore of the  Focus on the Family  group, have argued that the medical definition of conception should include fertilization. [ 16 ]


Finally, the standard historical method of counting the  duration of pregnancy  begins from the last menstruation and this remains common with doctors, hospitals, and medical companies. [ 17 ]  This system is convenient because it is easy to determine when the last menstrual period was, while both fertilization and implantation occur out of sight.  An interesting consequence is that the dating of pregnancy measured this way begins two weeks before ovulation.


Although many  anti-abortion  advocates have argued that both pregnancy and status of a separate human life beginning happen at fertilization, several examples also exist of people within those movements taking alternate views. For example, doctor and social activist  Bernard Nathanson  wrote in his 1979 work  Aborting America  that a confirmed moment of implantation should be considered the point at which a distinct human being exists. He specifically stated (note that 'alpha' is his  shorthand  for an organized group of cells), "Biochemically, this is when alpha announces its presence as part of the human community by means of its hormonal messages, which we now have the technology to receive... know[ing] biochemically that it is an independent organism distinct from the mother." [ 18 ]


In August 2008, the  U.S. Department of Health and Human Services  proposed a regulation to protect certain actions of health workers: refusal to provide patient services that the health workers believe to be abortifacient.  The ban on discrimination against these employees would apply to all organizations that receive grant money from HHS.  A draft version leaked in July proposed that the U.S. federal government define abortion as including "termination of [human] life... before... implantation."  The official proposal dropped the definition of abortion, instead leaving it to the objecting individual to define abortion for him- or herself.  Groups on both sides of the controversy believe the ban is intended to allow health workers to refuse to dispense IUDs and hormonal contraceptives, including emergency contraception.  It has drawn widespread criticism from major medical and health groups. [ 19 ] [ 20 ] [ 21 ]


In the past, pregnancy has been defined in terms of conception.  For example,  Webster's Dictionary  defined "pregnant" (or "pregnancy") as "having conceived" (or "the state of a female who has conceived"), in its 1828 and 1913 editions. [ 22 ]   However, in the absence of an accurate understanding of human development, early notions about the timing and process of conception were often vague.


Both the 1828 and 1913 editions of  Webster's Dictionary  said that to "conceive" meant "to receive into the womb and ... begin the formation of the embryo." [ 22 ]   However most references say that it was only in 1875 that  Oskar Hertwig  discovered that fertilization includes the penetration of a spermatozoon into an ovum.  Thus, the term "conception" was in use long before the details of  fertilization  were discovered.  By 1966, a more precise meaning of the word "conception" could be found in common-use dictionaries: the formation of a viable  zygote . [ 23 ]


In 1959, Dr. Bent Boving suggested that the word "conception" should be associated with the process of implantation instead of fertilization. [ 24 ]  Some thought was given to possible societal consequences, as evidenced by Boving's statement that "the social advantage of being considered to prevent conception rather than to destroy an established pregnancy could depend on something so simple as a prudent habit of speech."  In 1965, the  American College of Obstetricians and Gynecologists  (ACOG) adopted Boving's definition: "conception is the implantation of a fertilized ovum." [ 25 ]


The 1965 ACOG definition was imprecise because, by the time it implants, the embryo is called a  blastocyst , [ 26 ]  so it was clarified in 1972 to "Conception is the implantation of the blastocyst." [ 27 ]  Some dictionaries continue to use the definition of conception as the formation of a viable zygote. [ 28 ]


Birth control methods usually prevent fertilization. [ 29 ]  This cannot be seen as  abortifacient [ 30 ]  because, by any of the above definitions, pregnancy has not started. [ 31 ]  However,  emergency contraception  might have a secondary effect of preventing implantation, thus allowing the  embryo  to die. [ 32 ] [ 33 ] [ 34 ]  Those who define pregnancy from fertilization subsequently may conclude that the agents should be considered  abortifacients . [ 35 ]


Speculation about post-fertilization mechanisms is widespread, even appearing on patient information inserts for hormonal contraception, but there is no clinical support. One small study, using fourteen women, might be considered as providing evidence of such an effect for IUDs [ 36 ]  and a study of the  combined oral contraceptive pill  has been proposed. [ 37 ]


A related issue that comes up in this debate is how often fertilization leads to an established,  viable pregnancy . [ citation needed ]  Research in in-vitro fertilization patients suggests that fertilized embryos fail to implant some 30% to 70% of the time, although it is unknown whether this rate corresponds to inherently low human implantation rates (in natural conception) or to an altered physiological state. [ 47 ] [ 48 ]  Of those that do implant, about 25% suffer early pregnancy loss by the sixth week  LMP  (after the woman's Last Menstrual Period), and an additional 7% miscarry or are stillborn. [ 49 ]  As a result, even without the use of  birth control , between 50% and 70% of  zygotes  never result in established pregnancies, much less birth.


The intention of a woman to prevent pregnancy is an important factor in whether or not the act of contraception is seen as abortive by some  anti-abortion  groups. Hormonal contraceptives have a possible effect of preventing implantation of a blastocyst, as discussed previously. Use of these drugs with the intention of preventing pregnancy is seen by some  anti-abortion  groups as immoral. This is because of the possibility of causing the end of a new human life. [ 50 ]


However, hormonal contraception can also be used as a treatment for various medical conditions. When implantation prevention is unintentionally caused as a side effect of medical treatment, such  anti-abortion  groups do not consider the practice to be immoral, citing the bioethical  principle of double effect . [ 51 ]  Likewise, when a hormonal contraceptive is used with the intention of preventing fertilisation, the intended reduction in  implantation failures , miscarriages and deaths from childbearing may outweigh the possibility that the method might cause some implantation failures. [ citation needed ]


A related application of the principle of double effect is  breastfeeding . Breastfeeding greatly suppresses ovulation, but eventually an ovum is released. Luteal phase defect, caused by breastfeeding, makes the uterine lining hostile to implantation and as such may prevent implantation after fertilization. [ 42 ]  Some pro-choice groups have expressed concern that the movement to recognize  hormonal contraceptives  as abortifacient will also cause breastfeeding to be considered an abortion method. [ 52 ] [ 53 ]


A protein called  early pregnancy factor  (EPF) is detectable in a woman's blood within 48 hours of ovulation if fertilization has occurred. However, testing for EPF is time-consuming and expensive; most early pregnancy tests detect  human chorionic gonadotropin  (hCG), a hormone that is not secreted until after implantation. Defining pregnancy as beginning at implantation thus makes pregnancy a condition that can be easily tested. [ citation needed ]


The distinction in  ethical value  between existing persons and  potential future persons  has been questioned. [ 54 ]  Subsequently, it has been argued that contraception and even the decision not to procreate at all could be regarded as immoral on a similar basis as  abortion . [ 55 ]  In this sense, beginning of pregnancy may not necessarily be equated with where it is ethically right or wrong to assist or intervene. [ citation needed ]  In a  consequentialistic  point of view, an assisting or intervening action may be regarded as basically equivalent whether it is performed before, during or after the creation of a human being, because the result would basically be the same, that is, the existence or non-existence of that human being. [ citation needed ]


Compulsory sterilization , also known as  forced  or  coerced sterilization , refers to any government-mandated program to  involuntarily   sterilize  a specific group of people. Sterilization removes a person's capacity to reproduce, and is usually done by surgical or  chemical  means.


Purported justifications for compulsory sterilization have included  population control ,  eugenics , limiting the spread of  HIV , and  ethnic genocide .


Several countries implemented sterilization programs in the early 20th century. [ 1 ]  Although such programs have been made illegal in much of the world, instances of forced or coerced sterilizations still persist.


Governmental family-planning programs emerged in the late 1800s, and have continued to progress through the 21st century. During this time, feminists began advocating for reproductive choice, but eugenicists and hygienists were advocating for low-income and disabled peoples to be sterilized or have their fertility tightly regulated, in order to "clean" or "perfect" nations. [ 2 ] [ 3 ]  The second half of the 20th century saw national governments' uptake of  neo-Malthusian  ideology that directly linked population growth to increased (and uncontrollable) poverty, which, during the embrace of capitalism, meant that countries were unable to economically develop due to this poverty. [ citation needed ]


Much of these governmental population control programs were focused on using sterilization as the main avenue to reduce high birth rates, even though public acknowledgement that sterilization made an impact on the population levels of the developing world is still widely lacking. [ 4 ]  Early population programs of the 20th century were marked as part of the eugenics movement, with  Nazi Germany's programs  providing the most well-known examples of sterilization of disabled people. [ 5 ]  In the 1970s, population control programs focused on the "third world" to help curtail over population of poverty areas that were beginning to "develop" (Duden 1992).


As of 2013, 24 countries in Europe required sterilization for legal gender recognition and 16 countries did not provide for any possibility to change legal gender at all, which meant that transgender people could have challenges applying for jobs, opening bank accounts, boarding planes, or may not be able to do these things at all. [ 6 ]  Disabled women in Europe are also common targets of forced sterilization. "'So many times, you hear it’s in the best interest of the woman,' said  Catalina Devandas Aguilar , a former  United Nations  special rapporteur for disability rights. 'But often, it’s because it’s more convenient for the family or the institution that takes care of them.'" [ 7 ]


On 1 February 2013, "United Nations Special Rapporteur on Torture (SRT) issued a report on abusive practices in health care settings that has important implications for LGBT people and people with intersex conditions" and: [ 8 ]  In section 88, the SRT says States should:


repeal any law allowing intrusive and irreversible treatments, including forced genital-normalizing surgery, involuntary sterilization, unethical experimentation, medical display, "reparative therapies" or "conversion therapies", when enforced or administered without the free and informed consent of the person concerned. He also calls upon them to outlaw forced or coerced sterilization in all circumstances and provide special protection to individuals belonging to marginalized groups. [ 8 ]


In May 2014, the  World Health Organization ,  OHCHR ,  UN Women ,  UNAIDS ,  UNDP ,  UNFPA , and  UNICEF  issued a joint statement on "Eliminating forced, coercive, and otherwise involuntary sterilization". The report references the involuntary sterilization of a number of specific population groups. [ citation needed ]  They include:


The report recommends a range of guiding principles for medical treatment, including ensuring patient autonomy in decision-making, and ensuring non-discrimination, accountability, and access to remedies. [ 12 ]


Human population planning is the practice of artificially altering the rate of growth of a human population. Historically, human population planning has been implemented by limiting the population's  birth rate , usually by government mandate, and has been undertaken as a response to factors including high or increasing levels of  poverty ,  environmental concerns , religious reasons, and  overpopulation . While population planning can involve measures that improve people's lives by giving them greater control of their reproduction, some programs have exposed them to exploitation. [ 13 ]


In the 1977 textbook  Ecoscience: Population, Resources, Environment , authors Paul and Anne Ehrlich, and  John Holdren  discuss a variety of means to address human overpopulation, including the possibility of compulsory sterilization. [ 14 ]  This book received renewed media attention with the appointment of Holdren as Assistant to the President for Science and Technology, Director of the White House  Office of Science and Technology Policy , largely from conservative pundits who have published scans of the textbook online. [ 15 ]  Several forms of compulsory sterilization are mentioned, including the proposal for vasectomies for men with three or more children in India in the 1960s, [ 16 ]  sterilizing women after the birth of their second or third child, birth control implants as a form of removable, long-term sterilization, a licensing system allotting a certain number of children per woman, [ 17 ]  economic and quota systems of having a certain number of children, [ 18 ]  and adding a sterilant to drinking water or food sources, although the authors are clear that no such sterilant exists nor is one in development. [ 19 ]  The authors state that most of these policies are not in practice, have not been tried, and most will likely "remain unacceptable to most societies." [ 19 ]