Brigitte Nielsen is pregnant at 54, and people have questions

Brigitte Nielsen, star of Red Sonja, Beverly Hills Cop II and, more recently, The Surreal Life, is going to be a mom again at 54.

The Danish-Italian actress announced her fifth pregnancy via social media posts, proudly showing off her baby bump in a white body-con top and pink sweater on Monday. She wrote, simply, “family getting larger.”

She followed up today with a second post that she captioned “happy time.”

Nielsen, who has been married five times, is already mom to four sons: Raoul Meyer Jr., 23, Douglas Meyer, 25, Killian Marcus Nielsen, 28, and Julian Winding, 34. This will be her first child with 39-year-old husband Mattia Dessì, whom she married in 2006.

Her fans offered congratulations, asked questions, and shared their own hopes for a later-in-life pregnancy on her Instagram posts and in tweets.

“Congrats love! Gives me hope I turn 40 this year,” wrote yahzarah.

A commenter called n_f_silva shared the sentiment, writing, “Gives me hope!!!!!!! I am 44 and want more kids!!!! Did you get pregnant naturally???”

Many people just wanted to know how?

“Best wishes for a healthy baby, and would love to know if it’s your own egg or not just for my own interest,” genalog asked.

“Whoa you are brave! Can you tell us how is that possible? I never planned on having kids and was told that “after 36 is too old and unsafe,” wrote tatichristofferson.

Women do get pregnant naturally when they’re over 40, but, “it’s just very unlikely,” Zev Williams, associate professor of obstetrics and gynecology at Columbia University Medical Center, told Yahoo Lifestyle for an earlier story. “In fact, women over the age of 40 have high rates of unintended pregnancies due to taking fewer precautions on the belief that pregnancy isn’t possible.”

But the chance of conceiving normally drops around age 42 and 43. “It’s not that fertility disappears at a certain age, but rather the decline is a gradual process,” says Williams. “For a 28-year-old woman, about 25 percent of her embryos are chromosomally abnormal, and for a 44-year-old woman, that number rises to 90 percent.”

Given that a 45-year-old woman has less than a 1 percent chance of getting pregnant using her own eggs, it’s likely Nielsen had some type of fertility assistance, such as in vitro fertilization (IVF), a process that involves extracting eggs and sperm from a couple (or from donors), combining them in a laboratory, and then transferring them to the uterus. She also could have frozen her eggs years ago; they would then be thawed, fertilized, and transferred to her uterus, so she would be essentially using eggs from her younger self.

Read more from Yahoo Lifestyle:

• Cardi B Explains Why She Kept Her Pregnancy a Secret

• Jessie James Decker — and her insane eyelashes — welcomes baby No. 3

• The problem with celebrity baby Instagram accounts, like the one for True Thompson

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