When we think of age and fertility we usually think about a woman’s age. But a man’s age can matter too, according to a recent article in Self magazine. This article was prompted by the pregnancy created by John Stamos, 54, and his wife, Caitlin McHugh.
“In general, maternal and paternal age do impact fertility rates and after age 40, fertility rates decline,” Thomas L. Toth, M.D., an associate professor of obstetrics, gynecology, and reproductive biology at Harvard Medical School, told SELF. “However, it appears that the decline is not nearly as significant in the male patient as the female patient.” There are plenty of famous older dads to back that up: George Clooney was 56 when his twins were born and Hugh Hefner was 65 when his youngest son was born.
One reason why guys are fertile later in their lives than women is because sperm are constantly in the process of regenerating (a full cycle takes up to three months), Jennifer Hirshfeld-Cytron, M.D., director of fertility preservation at Fertility Centers of Illinois, tells SELF. Women, on the other hand, are born with a set number of follicles (immature eggs) that die, decrease in quality, or are lost to menstruation as time goes on. However, the concentration of sperm can go down, along with the actual volume of semen a man produces, Dr. Toth says. The shape of his sperm and motility (meaning, how his swimmers swim) can be impacted as well. If a man is struggling with these, it could lower his overall fertility. Those changes to sperm quality tend to depend on men’s overall health, Dr. Hirshfeld-Cytron says. For instance, medications that men may take to treat hypertension and diabetes can impact sperm, and having heart disease can negatively impact a man’s sperm, she says.
According to recent research, there may be some genetic changes happening as a man ages. Studies have found small increases in the likelihood of having a baby that goes on to develop autism, bipolar disorder, or psychosis as paternal age goes up (above age 45). But the overall risks for these conditions are low, and these population studies can’t determine an exact cause and effect, only a correlation between a father’s age and the risks for these issues. Overall, “this isn’t something to worry about,” Dr. Hirshfeld-Cytron says.
Fortunately today both men and woman can preserve their peak fertility through sperm and egg freezing. This is not something men usually think about. But it is certainly on the minds of many women as they get into their late 30’s and early 40’s.