Brigitte Nielsen is pregnant with her fifth child at 54 years old.

The model, actress, and reality TV star is already mother to four sons, 34-year-old Julian, whom she has with first husband Kasper Winding, 28-year-old Killian with Mark Gastineau, and 25-year-old Douglas and 23-year-old Raoul Jr., whom she has with fourth husband Raoul Mayer.

But now, 23 years after giving birth to her youngest child, she has revealed she is expecting once again, in what will be her first child with fifth husband Mattia Dessi.

The star announced the news in two separate posts on Instagram this week, which show off her burgeoning baby bump.

On one, she wrote: ''family getting larger #me #family #brigittenielsen #babybump (sic)''

Whilst on the second she added: ''happy time ❤️ positive vibes #happyness #positivevibes (sic)''

The 'Cobra' actress has caused a stir on social media with her pregnancy announcement, with many fans calling her an ''inspiration'' for having another child later in her life.

Responding to one fan, Brigitte wrote: ''Nobody has the rights to lead your own decision unless you allow them to do so. You're the only one in charge of yourself and your own happiness. Best of luck!''

Brigitte has been married to Mattia since 2006, but was previously wed to Kasper for a year from 1983 to 1984, before she enjoyed a two-year marriage to Sylvester Stallone from 1985 to 1987, followed by Sebastian Copeland in 1990 until 1992, and then Raoul from 1993 to 2005.