Baby making sounds so easy. But while conception after sex certainly happens, it’s not a given. “For a woman to become pregnant, lots of different factors need to line up,” says M. Max Ezzati, M.D., a reproductive endocrinologist at the Palo Alto Medical Foundation.
Medical, genetic, environmental, lifestyle and other factors can hinder fertility—and men are just as prone as women. “About 15 percent of infertility is unexplained,” says Alex Kim, M.D., an infertility specialist with the Palo Alto Medical Foundation. “Of the remaining 85 percent, roughly 30 percent is solely related to the woman while 30 percent is linked to the man. The remainder are a combination.”