Sarah Jessica Parker's chosen surrogate mother is reportedly a bisexual rocker.

The 'Sex and the City' actress and husband Matthew Broderick are set to become parents to twin girls and sources claim the woman carrying their babies has pink hair and tattoos.

The pregnant female has been identified by America's Star magazine as 26-year-old Michelle Ross, who is said to have previously acted as a surrogate for a gay couple and has a four-year-old son of her own.

Michelle wrote on her MySpace profile: "I have had pink hair and tattoos and spiked collars. My favourite shoes are five-inch black spike heels which lace up the front. I love metal and rock down to the bones."

Michelle's ex-husband Joseph Erker - who has reportedly looked after the couple's son Brayden since their 2006 divorce - claims she has a symbol of bisexuality tattooed on her wrist.

Referring to Michelle's overlapping pink and blue triangle inking he said: "She told me that is what it stands for, she's bi."

Joseph also alleges Michelle "discovered a dark side in herself" after losing the couple's first baby, adding the heartbreak is behind her decision to help other people.

He added: "She said she wanted to become a surrogate to help people who couldn't have children of their own."

Michelle has refused to confirm if she is acting as a surrogate for Sarah Jessica and Matthew.

(China Daily/Agencies May 8, 2009)