Technically, male infertility is defined simply as the inability to fertilize a female egg. Still, a man who gets the diagnosis could be experiencing a range of problems, Jeff Foster, a physician specializing in men’s health, tells Inverse. Foster is also the author of Man Alive: The Health Problems of Men and How to Fix Them and spoke to Inverse about this exceedingly common diagnosis.
Foster says that a person’s lifestyle may be the root of their infertility challenges in some cases. In other cases, genetic or biological issues may be responsible. Only 10-15 percent of men with fertility problems experience Azoospermia or a complete lack of sperm.