Angelina Jolie poses with her husband Brad Pitt as they arrive for the world premiere of his film World War Z in London June 2, 2013.[Photo/Agencies]

Photos: 'World War Z' premieres in London

Angelina Jolie made her first public appearance since announcing her double mastectomy on Sunday, joining fiance Brad Pitt on the red carpet in London where she welcomed the debate on women's health that the surgery had sparked.

The Oscar-winning actress has stayed out of the spotlight since announcing her operation in a New York Times column last month, saying the decision was made after finding she carried a gene giving her an 87 percent chance of getting breast cancer.

The 37-year-old mother of six, praised for her courage in publicly announcing her surgery, is now reported to be planning another operation to remove her ovaries as the BRCA1 gene also gives her a 50 percent chance of ovarian cancer.

On the red carpet for the world premiere of Pitt's latest movie, zombie blockbuster "World War Z", Jolie praised her partner as being "a wonderful man and a wonderful father.

"I'm very, 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 told reporters.

"After losing my mom to these issues, I am very grateful for it," added the American actress, wearing a long black, backless Yves Saint Laurent dress.

Jolie's mother, actress Marcheline Bertrand, died from ovarian cancer in 2007 at the age of 56 and her aunt, 61-year-old Debbie Martin, died last week as a result of breast cancer.

Jolie missed her aunt's funeral to accompany Pitt to London for the premiere of "World War Z", an adaptation of Max Brooks' 2006 apocalyptic novel.

Pitt's production company Plan B Entertainment bought the screen rights to the novel about six years ago and it is one of the big box office releases this summer, but it is under pressure to perform before even opening.

It was due to be released late last year but suffered setbacks amid reports that the budget had ballooned above $200 million and Pitt clashed with director Marc Forster.