Think men can wait forever to have children? Science says “Think again.”

According to an article published on the Daily Beast yesterday, men who want children “eventually” may want to go ahead and get on that.

“What doctors call the ‘paternal age effect’—a condition that affects the children of men older than 35, and especially after 40—may lead to an increased incidence of all sorts of serious problems like dwarfism, Marfan syndrome (a connective-tissue disorder), and Apert syndrome (in which the skull and other body parts are malformed),” warns author Sarah Wildman.

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B-but… we’re men. Isn’t our ability to have healthy children with much younger women for the rest of our lives our birthright? Not according to professor of developmental and regenerative biology at Mount Sinai School of Medicine, Ethylin Jabs (ironically also the name of the 10th level half-elven illusionist that I play as part of my weekly Dungeons and Dragons game — and activity which represents my extended adolescence and belief that children can wait).

“Sperm is made like any cell in the body,” says Jabs. “Your DNA is replicated, and then the cell splits into two new cells, so this process of spermatogenesis creates new sperm, there is ongoing replication of DNA … With each ejaculate, men make millions of new sperm, but as they grow old the machinery that allows this process to occur isn’t as effective as it was when they were young. It doesn’t work as well. So errors get introduced.”

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I remember my first experience with “viral” sharing — my brother made me a cassette copy of seminal crank callers, the Jerky Boys, first compilation. Legend had it that this tape was a copy of a copy of a copy of a copy, going all the way back to the original recorded pranks. By the time it got to me, it sounded like hell and the copies I made for my friends sounded even worse. This is, apparently what happens to our sperm as we age.

What are men who want to father healthy children to do? The same thing that women who want children have been doing — either make children a priority now, or freeze their zygotes. In fact, Mandy Katz-Jaffe at the National Foundation for Fertility Research encourages healthy men young men to freeze their sperm.

“Men in their 30s can make a choice in regards to freezing their sperm because they haven’t met women of their dreams or their career [isn’t ready] or they don’t want children right now,” explains Katz-Jaffe, “Freezing sperm can improve their chances of having a healthy offspring when they do want to have children. It’s a lot easier for men to give a sperm sample [than for women to freeze eggs], and it’s a lot cheaper. It is an insurance policy. You might not need to cash it in, but you might.”

[DailyBeast]