Couples With Infertility Problems Often Focus on a Woman's Biological Clock and Forget About the Male Contribution... It appears that men older than 35 are twice as likely to be infertile as men younger than 25. As men age, both the number and quality of their sperm decline — so older men become less likely to father a child and more likely to father a child with schizophrenia, Down syndrome, or other problems... men 40 years or older are almost six times more likely to have a child with an autism disorder than men younger than 30. Miscarriages also are more common as dad gets older... Given that 20 percent of couples are infertile because of abnormal or absent sperm and that 27 percent of infertile couples have a combination of male and female factors, it makes sense to evaluate a man's equipment, so to speak, sooner rather than later. (Full story here)