Hilary Duff has undergone acupuncture in preparation for giving birth.

Hilary Duff is trying to encourage her baby's birth

Hilary Duff is trying to encourage her baby's birth

The 36-year-old actress is pregnant with her fourth child, and she has tried the treatment - which involves fine needles inserted at certain points in the body - to give her baby a nudge.

Alongside a selfie with needles in her forehead, head and cheekbones, she wrote on Instagram: "Pretty slow week around here. And gently trying to give baby the eviction notice."

The 'Lizzie McGuire' star has daughters Mae James, three, and Banks Violet, five, with her husband Matthew Koma, as well as son Luca Cruz, 12, with ex-husband Mike Comrie.

She recently credited Matthew with giving her all the help and support she needs as they prepare to become parents again, while admitting having four children is a "wild choice".

She wrote on Instagram: "Four kids is a truly wild choice. And while you rage [sic] the farmers market with the kids after 4 nights of shows and late nights so I can get some sleep and not hear mom mom mama mommy mooooom just know this only works because of you."

She previously admitted having a big family means her home is typically defined by “mayhem and craziness”.

However, she told Shape magazine: “I love the pressure of being like, ‘How are we going to make it through this day?’

"And making it through the day and being like, ‘I don’t know how everyone is tucked in and fed and happy after all the things we’ve had to do today.' "

Referring to the concept of perfection while parenting, Hilary added she is “really good at being disappointed” in herself while raising a family.

She added: “You’re just wired to think that you are loaded with all the answers and all of the capability, (but) we’re still just human beings.”