File photo: The star has been married to Italian TV producer Mattia Dessì, 39, since 2006. Picture: AP

London - With four sons from three different men, Brigitte Nielsen’s personal life is already rather complicated.

And now the actress is about to make things even more tricky - by having another baby at the age of 54.

Nielsen, who was married to Sylvester Stallone for two years, announced the news on Thursday by posting pictures on social media which revealed her large bump.

Dressed in a tight white dress, she wrote: "Family getting larger".

The star has been married to Italian TV producer Mattia Dessì, 39, since 2006. He is her fifth husband.

READ: Twitter drags Brigitte Nielsen after announcing pregnancy at age 54

It is unclear whether the couple conceived using IVF or a donor egg but by the age of 45, women have just a one percent chance of becoming pregnant naturally. Menopause begins at around 51 for the average woman.

family getting larger ❤️ #me #family #brigittenielsen #babybump

A post shared by Brigitte Nielsen (@realbrigittenielsen) on

Copenhagen-born Nielsen is already mother to Julian, 34, Killian, 28, Douglas, 25, and Raoul, 23.

She was previously married to composer Kasper Winding from 1983 until 1984, actor Sylvester Stallone from 1985 until 1987 and photographer Sebastian Copeland from 1990 until 1992.

Her fourth husband – from 1993 to 2003 – was documentary writer Raoul Meyer.

Nielsen, whose best-known movies include 1985’s Rocky IV, 1986’s Cobra and 1987’s Beverly Hills Cop II, has also had relationships with Arnold Schwarzenegger and rapper Flavor Flav.

Neilsen, who is several months into her pregnancy, has managed to keep her news quiet until now. Last week she was photographed hiding her baby bump under a white top as she enjoyed lunch with Dessi in Los Angeles. 

She first came to the public’s attention in the early 1980s as a fashion model and appeared in Playboy several times. Her profile skyrocketed when she wed Stallone in 1985 and then went on to appear with him in Rocky IV and Cobra.

Nielsen has starred in a number of reality TV shows including Britain’s Celebrity Big Brother in 2015 alongside her former mother-in-law Jackie Stallone. In 2008 she took part in Celebrity Rehab with Dr Drew, which saw her and other celebrities deal with recovery from drug and alcohol addiction.