John Stamos, 54, will be a father — what are the risks for older dads?

John Stamos played uncle to three girls on television, but his real-life home is about to get fuller: He’s becoming a father at age 54.

People broke the news in this week’s cover story that the actor and his fiancée, Caitlin McHugh, 31, are pregnant with their first child, nearly two months after becoming engaged.

“We have the same morals and the same values, that all clicked nicely. So we said, ‘Oh, well, maybe we should have a family,’” Stamos told the publication, adding that McHugh wanted to conceive before their wedding, ‘Because you’re old.’”

Stamos will join a long list of older celebrity dads. In December 2016, Mick Jagger, then 73, welcomed his eighth child, with girlfriend Melanie Hamrick, who is more than four decades younger; In June, George Clooney, 56, became a father for the first time, of twins, with wife Amal Clooney, 39; and Billy Joel, 63, welcomed his third child in October, with wife Alexis, 35.

According to a study by Stanford University and published in the journal Human Reproduction, the average age of first-time fathers has increased from 27.4 in 1972 to 30.9 in 2015. What’s more, according to the press release, the number of men over age 40 who become fathers of newborns shot up from 4.1 percent to 9.9 percent. And the number of men over 50 spiked from .5 percent to .9 percent.

“Unlike women who are born with a certain number of eggs, men can produce sperm their entire lives until the day they die,” Shahin Ghadir, MD., founding partner of the Southern California Reproductive Center, tells Yahoo Lifestyle. “There are possible risks — studies have shown a mild correlation between autism and other chromosomal abnormalities, and older sperm, but they’re not clear-cut.”

Other potential risks: A 2006 study published in the journal Obstetrics & Gynecology found that women pregnant by partners who were 35 or older had almost three times as many miscarriages as women who conceived with men younger than 25.

And CNN reported that a study presented at a recent medical conference found that among couples who use in vitro fertilization (IVF), live birth rates among women younger than 40 decreased with the “increasing age of the male partner.”

There are also logistical pros and cons to older parenthood for both sexes — on the one hand, those who wait are likelier to be better educated and financially secure. However, older couples may have a smaller support system due to increasing pressure to care for their aging parents.

Of course, there is no perfect age for anyone to start a family, as long as it feels right. However, Ghadir offers this general advice: “We try to encourage both men and women to preserve their fertility before the age of 40.”

Read more from Yahoo Lifestyle:

• Are Hatchimals giving children chemical burns?

• Breastfeeding mom kicked off of Spirit Airlines flight: ‘It was humiliating to be chased off a plane’

• Trent Franks offered $5 million, but how much does hiring a surrogate really cost?

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