Men’s Biological Clocks

Wil Saletan notes that a new study shows that men over 40 have far more trouble impregnating women than their younger counterparts. And it’s not just diminished sex drive and/or sex appeal:

In a study of more than 1,900 couples, irrespective of the woman’s age, IVF attempts involving men 40 or older failed 70 percent more often than IVF attempts involving men younger than 30. Previous theory: Older men produce fewer kids because they get less sex. New theory: Older men produce fewer kids because they shoot more blanks. Feminist takes: 1) Ladies, stop blaming yourselves for IVF failure. 2) Ask not for whom the biological clock ticks, dude. (For Human Nature’s update on instant male fertility testing, click here. For abstinence and male fertility, click here. For smoking and male fertility, click here.)

This isn’t horribly surprising, as our bodies become generally less healthy with age. Still, the conventional wisdom has been that, since men produce new sperm constantly, this particular issue was not pressing.

So, perhaps those of us over 40 (I’m 40-1/2) should be considered post-pregnant?

FILED UNDER: Gender Issues, Health,
James Joyner
About James Joyner
James Joyner is Professor and Department Head of Security Studies at Marine Corps University's Command and Staff College. He's a former Army officer and Desert Storm veteran. Views expressed here are his own. Follow James on Twitter @DrJJoyner.


  1. DC Loser says:

    Wished that were true in my case. My wife and I had an “accident” when I was 45. Coulda saved a lot of money and pain if I didn’t need that vasectomy.

  2. Alan says:

    I wonder if they factored in the age of the female. I would guess that in most IVF attempts where the man was over 40, the woman was close to the same age. That might also account for the reduced pregnancy rate.

  3. RA says:

    I lost one of my testicles to cancer when I was 40. I conceieved one daughter when I was 46 and another daughter when I was 48.

    The only explanation I have is I am 100% Lithuanian. God invented strong drink to keep Lithuanians from ruling the world. LOL

  4. floyd says:

    note to those who worship statistics, “liars may figger, but figgers don’t lie”. i’ve always maintained that “statistics” is not science, but maybe it’s “political science” after all[lol]

  5. John Burgess says:

    Quantity of sperm may (or may not) decrease with male age. Quality, however, is a completely different issue. There are studies out there showing that sperm from older men has higher frequency of birth defects, for one thing.

    Truly defective sperm would have great difficulting in accomplishing conception, no matter the age of the producer.

  6. Jay says:

    Good thing for Deb we didn’t meet when I was younger. I might have given her a couple sets of triplets or something.