A Biological Clock for Guys?


The biological clock may no longer be ticking on just the woman’s side of the bed.

If current research is correct, a man’s baby-making alarm may start to ring not too long after a woman’s chimes its final warning toll — around age 40.

“I don’t want there to be a panic, but I think it’s safe to say that the father’s age should be one of many factors couples should put into the equation when planning a family,” says Karine Kleinhaus, MD, PhD, a researcher at Columbia University who recently spearheaded a study on paternal age and radiation exposure. There are a whole battery of environmental assaults that may accumulate over time, causing at least some of the reproductive issues we now attempt to link solely to age,” says McCulloh.

Silverman agrees, suggesting that much the way lifestyle practices affect the health of other systems in the body, such as the , so too might they affect male reproduction. “>

At least one study indicated that oxidative damage — one type of environmental assault — can increase chromosomal damage in sperm.

In animal research published in 2005 in the journal Fertility and Sterility, researchers found that not only was the DNA of sperm susceptible to oxidative damage, but the older the male, the more susceptible the sperm was to developing breaks in the DNA.

It is this kind of genetic upset that experts say could be behind some of the birth defects and other problems that until recently were thought to be exclusively related to the mother.

The American Society of Reproductive Medicine now recommends that sperm donors be men that are “ideally less than 40 years of age to minimize the potential hazards of aging.”

What Men Can Do

While evidence seems clear that at least the possibility of a male biological clock exists, not everyone believes it comes with a fertility alarm. Indeed, some experts cling steadfastly to the notion of omnipotent and virtually indestructible sperm at any age.

“I’m not at all convinced [age is a factor]. These are not prospective studies and you cannot pick the disease state and then work backwards. You can’t do it that way because you’re going to come up with the wrong conclusion. You may have the observation, but you don’t have the link,” asserts Andrew McCullough, MD, director of sexual health and male infertility at NYU Medical Center in New York City.

He tells WebMD that until there is a study that controls for all the variables — which may be impossible — all we have are assumptions and no proof.

“These are observations worth noting, but to say ‘Aha, this is the answer’ — well that’s a real stretch,” says McCullough.

Silverman comments that while the evidence may be too new to draw finite conclusions, he says the findings thus far are relevant and a portent of things to come.

“Eventually I believe we will have the research to show that when it comes to fathering a child, time isn’t always on a man’s side,” says Silverman.

In the meantime, as embryologist McCulloh points out, every man can protect his parenting potential at any age by taking better care of his overall health.

McCulloh tells WebMD, “If you don’t smoke, drink in moderation, exercise daily, and eat a healthy diet, you are likely to remain healthier in general — and that means a healthier reproductive system overall.”

Protecting the Health of Sperm

Experts also say men can take additional steps to protect the health of their sperm as well as their potency, at every age. Try the following:

Published Sept. 25, 2006.