Is Male Age Linked to Lower Chance of Conceiving?

What do Charlie Chaplin, Robert De Niro, and Pablo Picasso have in common? Sounds like the start of a bad joke, but the answer is: they were all fairly old when they became fathers.

The male biological clock

We all know about the female biological clock — fertility declines with age, and once menopause hits, that's it. Men, famously, don't have the same hard stop. Charlie Chaplin fathered a child at 73. Robert De Niro at 68. Clint Eastwood at 66. Steve Martin at 67. The list goes on.

But male age still matters

So does that mean age is irrelevant for men? Not quite. A study found that for each additional year of the male partner's age, his fertility tends to decrease by about 4% — and that effect is independent of the female partner's age, so it's not just a byproduct of older men having older partners.

What a gradual 4%-per-year decline actually looks like

Unlike the more defined decline women experience as they approach menopause, male fertility decline appears to be gradual and close to linear across the years, rather than dropping sharply at any particular age. That's part of why men can and do conceive well into their 60s and 70s — there's no equivalent hard stop. But a steady 4% per year adds up over a couple of decades, so it's a real factor, not a myth invented to make men share in the "aging" conversation. If you're navigating fertility with an older male partner, it's one more variable worth factoring in alongside female age, especially if other risk factors are already in the mix.

Reference

Horta et al. 2019. Human Reproduction, 34(12), 2523–2532.