Oscar-winning actress Angelina Jolie made her first public appearance since her double mastectomy.

She joined partner Brad Pitt, at the premiere of his film World War Z held at the Empire Leicester Square in London.

The 37-year old actress, looked stunning in a black open-back gown, with a sheer panelled fitted bodice and free-flowing skirt.

The mother-of-six discovered that she carried the BRCA1 gene mutation that leads to a risk of both breast and ovarian cancer. She "decided to be proactive and to minimise the risk."

The double mastectomy involved three surgeries over almost three months, including reconstruction surgery with implants. Jolie's mother, actress Marcheline Bertrand, died of breast cancer in 2007 at age 56.

"I'm very grateful for all the support and I have been very happy just to see the discussion of women's health expanded and that means the world to me," she said. "After losing my mum to these issues, I am very grateful for it."

Debbie Martin, the younger sister of Jolie's mother, died recently at the age of 61 at a clinic outside San Diego because of breast cancer.

"When she's faced with a problem - and we have known this was coming for some time - she takes it by the horns," Pitt said of Jolie, "I'm super-proud of her."

Jolie is also reportedly planning to undergo another operation to remove her ovaries as the BRCA1 gene also gives her a 50 percent chance of ovarian cancer.