Angelina Jolie says she has undergone a preventive double mastectomy after being told that she had an 87 percent risk of breast cancer, along with a 50 percent risk of ovarian cancer.

In an article published in the opinion section of Tuesday's New York Times, Jolie said her decision was informed by her mother's long fight against cancer. Marcheline Bertrand died in 2007 at age 56.

Jolie said she hoped that other women would find encouragement from her story. 

"I choose not to keep my story private because there are many women who do not know that they might be living under the shadow of cancer," Jolie said in the Times article. "It is my hope that they, too, will be able to get gene tested, and that if they have a high risk they, too, will know that they have strong options." 

Jolie, an Oscar-winning actress and activist, said she carries a gene, BRCA1, that increases the risk of breast and ovarian cancer. According to Jolie and a fact sheet from the Cancer Institute at Stanford Medicine, women with the BRCA1 gene have an average of a 65 percent lifetime risk for breast cancer, along with heightened risk of the cancer at an early age. Jolie is 37. 

Jolie said three months of medical procedures that the mastectomies involved were completed April 27. She said the surgery included implants to reconstruct her breasts.

She said that her partner, Brad Pitt, was present for the surgeries. She said her six children, who range in age from 11 to 4, saw nothing that made them uncomfortable.

"They can see my small scars and that’s it," Jolie wrote. "Everything else is just Mommy, the same as she always was. And they know that I love them and will do anything to be with them as long as I can."

Other famous women with the BRCA1 or BRCA2 genes have undergone preventive double mastectomies, including reality star Sharon Osbourne, wife of rocker Ozzy.

"I've had cancer before and I didn't want to live under that cloud," Osborne said in an interview last fall.

In January, Miss America contestant Allyn Rose, representing the District of Columbia, announced that she carries another genetic mutation -- not BRCA1 or BRCA2 -- and plans to have a double mastectomy after her year of serving as Miss D.C.

Friends and fans were quick to support Jolie via messages on Twitter. Actress Marlee Matlin called her "brave, honest (and) strong." And "Veronica Mars" star Kristen Bell praised Jolie's article as "admirable."

Slideshow: Angelina Jolie

Toby Melville / Reuters

Highlights from her Oscar-winning acting career, family life with Brad Pitt and worldwide humanitarian efforts.

Launch slideshow

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Sharon Osbourne.

Sharon Osbourne has taken firm, decisive steps to safeguard her health. The "America's Got Talent" judge revealed that she underwent a double mastectomy after doctors discovered she carried a gene that made her susceptible to breast cancer.

The news, which she shared in the latest issue of Hello! magazine, comes 10 years after Osbourne survived a battle with colon cancer.

TODAY Health: More women getting double mastectomies

"I've had cancer before, and I didn't want to live under that cloud," Osbourne, 60, tells the mag, as excerpted by the Daily Mail. "I decided to just take everything off, and had a double mastectomy."

The course of action she needed to take, she added, was a clear and swift one.

"For me, it wasn't a big decision, it was a no-brainer," she explained. "I didn't want to live the rest of my life with that shadow hanging over me."

Sharon Osbourne addresses America's Got Talent departure rumors

A big factor in her decision? Her new granddaughter, Pearl, whom son Jack Osbourne and his now-wife, Lisa Stelly, welcomed in April.

"I want to be around for a long time and be a grandmother to Pearl," she said. "I didn't even think of my breasts in a nostalgic way. I just wanted to be able to live my life without that fear all the time."

She also noted, "It's not 'pity me.' It's a decision I made that's got rid of this weight that I was carrying around."

Jack Osbourne diagnosed with multiple sclerosis

The intimate revelation arrives four months after Jack was diagnosed with multiple sclerosis.

Shortly afterward, she openly wept on "The Talk" about the impact the news had on her, while thanking everyone for their well wishes.

"He's doing really, really good, and I want to thank everyone for all their texts and goodwill and love they've sent to us." she said. "I really believe that vibes and prayer help."

Jack Osbourne welcomes a baby girl

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Sharon Osbourne couldn't fight back her tears Monday on "The Talk." The host could hardly get the words out speaking about her son Jack Osbourne's Sunday announcement that he has multiple sclerosis, but could hardly get any words out.

Photos from Us: Celeb health scares

"Jack will actually be here on Wednesday to talk about his diagnosis, but he's great," Sharon, 59, said between sobs on the CBS show. "He's doing really, really good and I want to thank everyone for all their texts and goodwill and love they send to us ..."

Jack, 26, revealed Sunday he has been diagnosed with the autoimmune disease that affects the brain and spinal chord. MS can cause problems with muscle control, vision, balance and thinking, but affects each patient differently. The former "Osbournes" star turned filmmaker just welcomed the birth of his first child, daughter Pearl, two months ago with fiancee Lisa Stelly.

Photos from Us: New star dads

After Sharon composed herself, she added, "Thank you to everyone for all their good wishes. It's been amazing -- but for Jack because I really believe that vibes of prayer help."

"And what I'm doing right now is not helping because I'm just feeling sorry for myself, and that is no good," she continued. "So we just have to think positively and get on with this show that we love."

Jack tweeted Sunday, "Thank you all so much for the kind and inspirational words. It means a lot. Adapt and overcome."

Photos from Us: TV dads we love

Other stars affected by the chronic disease include talk show host Montel Williams, actress Teri Garr and Michelle Obama's father, Fraser Robinsson III.

"My father has multiple sclerosis and I never knew him to be able to walk," Obama shared on "Late Show with David Letterman" in March. "But my dad worked so hard and he loved us so much. And I think from him, I learned absolute, complete unconditional love. The notion that kids don't need anything but to know that their parents adore them. I think that's the greatest gift they gave us -- their constant support and stability. ... There wasn't anything my dad wouldn't do for us."

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Sharon Osbourne at the 2012 Golden Globes.

Sharon Osbourne's never been a shrinking violet where husband Ozzy's musical career is concerned, but she's now saying that rumors she interfered with the upcoming Black Sabbath reunion are false.

Ozzy’s better half tweeted yesterday, “I am not in any position to hire or fire anyone in Black Sabbath. I don't manage the band, I manage my husband.”

Anger first began to mount last week, when Sabbath drummer Bill Ward wrote on his Facebook page: “I am unable to continue unless a 'signable' contract is drawn up; a contract that reflects some dignity and respect toward me as an original member of the band.”

Though details are sparse, it seems Ward believes he was slighted in terms of his relevance to the quartet. He went on to note, “If I sign as-is, I stand to lose my rights, dignity and respectability as a rock musician.”

Black Sabbath’s response? Too bad. In lieu of further negotiations, the band stated they would simply move on without him. Accordingly, it’s been Facebook to Facebook combat between the two, with the group retorting soon after on their own page, “We were saddened to hear yesterday via Facebook that Bill declined publicly to participate in our current Black Sabbath plans...We have no choice but to continue recording without him although our door is always open...”

Whether or not Sharon Osbourne was involved, many fans are taking Ward's side, saying they don’t believe in a reunion without all the group’s original players. A drum impresario, Ward was a vital part of the band’s conception in 1969.

Wrote fan Max Far on Black Sabbath's Facebook page: "If Bill ain't on board, I'm not either. Don't let Sharon screw the fans out of what we want!"

Should Black Sabbath reunite without Ward? Tell us on our Facebook page. 

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