A magazine cover photo of Angelina Jolie breastfeeding one of her newborn twins may have turned the superstar actress into a role model for new mothers.

The photo, taken by Jolie's partner Brad Pitt, will adorn the November issue of W magazine. Other family pictures taken by Pitt in the weeks after the birth in July of twins Vivienne Marcheline and Knox Leon will appear inside.

"I think it is fabulous. Seeing a celebrity like Angelina Jolie breastfeed can be a role model to encourage women to make a choice that is wonderful for their baby," said Andi Silverman, mother of two and author of Mama Knows Breast.

"Breasts are used to sell all sorts of products, so to see them used the way nature intended can only be a great thing," Silverman said.

But while breastfeeding support groups and mums celebrated Jolie's public statement, one expert said the picture felt like voyeurism, especially given Jolie's sex symbol status in movies like Wanted and Lara Croft: Tomb Raider.

About 70 per cent of American mothers breast-feed their newborns but the rate falls dramatically after six months, according to official figures.

Jolie, 33, is not the first celebrity to be photographed nursing her baby. Model Jerry Hall appeared on the pages of Vanity Fair in 1991 breast-feeding Gabriel, her son with Mick Jagger.

But that was a generation ago, and Jolie's global influence as a style-setter and through her humanitarian travels and support of kids in third world countries, ensured the impact of the photo of her special moments with her baby.

"The response from mums we have seen is that if someone as popular, beautiful and together as Angelina is breastfeeding her children, it inspires other women to do so themselves," said Dr Shannon Fox, a psychotherapist with the www.momlogic.com website.

Little is seen in the picture of the act of breastfeeding. It shows Jolie smiling, while a tiny hand is just visible at bottom of the frame.

But Fox said the cover photo sends a second message.

"The problem is that she is also an international sex symbol. So whether or not she says 'This is a beautiful way of nurturing my baby', every man who sees that photo will see those breasts as sexual."

La Leche League International, the world's oldest breastfeeding support organisation, said the photo was particularly welcome as Jolie has twins.

"Mothers of twins report it takes a lot of time, effort and physical energy to breastfeed. I think the picture is beautiful," said La Leche League International spokeswoman Jane Krouse.

Reuters