The most common reason to be child-free reported in studies, by far, was a desire to be free of childcare duties and higher opportunities for personal growth and spontaneity. Women were especially likely to be concerned by overpopulation, worry about children’s lives in our current world, and about their ability to parent. Some child-free people are worried about the implications of pregnancy and birth and find it traumatic or something to avoid, which was the cement for their child-free foundation. Others still have concerns about work interfering with their family life and make the decision based on that.

http://fembotmag.com/2015/09/25/the-stigma-of-being-child-free-by-choice/