Hollywood actress Angelina Jolie has written about her decision to have a double mastectomy.

The Oscar-winner was found to have a faulty gene which sharply increases the chance of her developing breast and ovarian cancer.

Jolie, who lives with Hollywood star Brad Pitt, says in an article for the New York Times that her mother fought cancer for 10 years before her death.

She writes: “My doctors estimated that I had an 87% risk of breast cancer and a 50% risk of ovarian cancer, although the risk is different in the case of each woman.

“Only a fraction of breast cancers result from an inherited gene mutation. Those with a defect in BRCA1 have a 65% risk of getting it, on average.

“Once I knew that this was my reality, I decided to be proactive and to minimise the risk as much I could. I made a decision to have a preventive double mastectomy.”

Angelina Jolie, 37, who has six children – three by Pitt and three adopted – goes on: “On April 27, I finished the three months of medical procedures that the mastectomies involved.

“During that time I have been able to keep this private and to carry on with my work. But I am writing about it now because I hope that other women can benefit from my experience.

“Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness.

“But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action.”

Jolie reveals she had the first of three procedures on February 2. The major surgery “where the breast tissue is removed and temporary fillers are put in place” was carried out two weeks later.

Nine weeks later she had breast implants. “There have been many advances in this procedure in the last few years, and the results can be beautiful,” she writes.

She adds: “I wanted to write this to tell other women that the decision to have a mastectomy was not easy. But it is one I am very happy that I made.

“My chances of developing breast cancer have dropped from 87% to under 5%. I can tell my children that they don’t need to fear they will lose me to breast cancer.”

In the article, titled My Medical Choice, the star reveals that Pitt was by her side “for every minute” of all three procedures.

“I am fortunate to have a partner, Brad Pitt, who is so loving and supportive,” she writes. “So to anyone who has a wife or girlfriend going through this, know that you are a very important part of the transition.

“Brad was at the Pink Lotus Breast Center where I was treated, for every minute of the surgeries. We managed to find moments to laugh together.

“We knew this was the right thing to do for our family and that it would bring us closer. And it has.”

Jolie, who is one of the world’s highest paid performers, says the cost of getting tested for BRCA1 and another faulty gene, called BRCA2, is more than $3,000 (nearly £2,000) in the US and that this “remains an obstacle for many women”.

NHS guidelines in the UK recommend that anyone who is at ‘high risk’ of developing breast cancer at some point in their life be gene tested.

The risk level is dependent on close blood relatives – from one side of a family – having breast cancer. Factors that may increase risk, according to the National Institute for Health and Clinical Excellence (NICE) guidelines, include a family member being diagnosed with breast cancer at a young age or having cancer in both breasts, having a male relative with breast cancer and if there is also ovarian cancer in the family.

Michelle Heaton said Jolie’s decision to publicise her double mastectomy would be very important in giving support and encouragement to other women in a similar situation.

The Liberty X singer, who underwent a double mastectomy last year, told : “I think she is 100% right be coming out and letting everybody know what she has been through and how she has come out the other end.”

She said she hoped the press coverage of her own experience and that of Jolie and former X-Factor judge Sharon Osbourne, who revealed in November she had undergone the same operation after finding out she carried the faulty breast cancer gene, over the last six months would “have a positive impact for women out there who are deciding whether they should be tested for this gene or not”.

Jade Goody’s high-profile battle with cancer prompted a spike in cervical screening before and after the Big Brother star’s death in 2009.

Jolie, daughter of Hollywood luminary Jon Voight, has appeared in dozens of films including 2010’s “The Tourist” and “Salt,” the “Tomb Raider” films, and 1999’s “Girl, Interrupted,” for which she won an Academy Award.

But she has appeared more often in the news in recent years for her power coupling with Pitt and her charitable work with refugees as a United Nations ambassador.

Foreign Secretary William Hague, who in March visited refugee camps in the Democratic Republic of Congo with Jolie as part of a campaign to highlight the problem of mass rape in conflict areas, said she was “a brave lady” who would be “an inspiration to many”.

Mr William Hague told : “She is a courageous lady and a very professional lady. She’s done a lot of work with me in recent months.

“She also came over to the G8 foreign ministers’ summit in London to work with me on our initiative on preventing sexual violence in conflict and travelled with me through some difficult places in the Congo.

“She gave no sign that she was undergoing such treatment and I think she’s a very brave lady, not only to carry on with her work so well during such treatment, but also to write about it now and talk about it. I think that she’s a brave lady and will be an inspiration to many.”

Wendy Watson, who founded the National Hereditary Breast Cancer Helpline, also welcomed Jolie’s decision to publicise her double mastectomy. Mrs Watson, from near Bakewell, Derbyshire, under went a double mastectomy in 1992, aged 37.

“It is excellent, because it is the highest profile you can get for it,” she said.

“It raises the profile for other women to look to if they have a family history and would benefit from being screened more frequently, or having surgery or having a genetic test.

“She (Jolie) probably feels that under going the operation is common sense but it probably does take a certain amount of courage to face it.”

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