Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Using this as a birth ball

Ball is great, seems very sturdy and is a pretty blue color. I'm using it as a birth ball--the official "birth balls" are double the price! Only complaint is the extremely harsh chemical smell...it has definitely lessened in the week since we purchased, but I'm planning on wiping it down with soap and water to hopefully get the rest of it out. It was overwhelming at first.