Angelina Jolie has revealed that she underwent a double mastectomy after learning that she carried a gene that dramatically increased her risk of getting breast cancer.

In an op-ed piece for the New York Times titled “My Medical Choice,” the 37-year-old actress opened up about the reasons for her decision.

Because she carries a mutation of the BRCA1 gene, “My doctors estimated that I had an 87 percent risk of breast cancer and a 50 percent risk of ovarian cancer, although the risk is different in the case of each woman.”

[Read “Breast Cancer Gene: Should You be Tested?”]

Her own mother, Marcheline Bertrand, died of ovarian cancer in 2007 at the age of 56, before the birth of Jolie’s twins Knox and Vivienne.

Jolie wrote that the operation made it easier to reassure her family (she and partner Brad Pitt have six children together), that she wouldn’t suffer a similar fate.

“We often speak of “Mommy’s mommy,” and I find myself trying to explain the illness that took her away from us. They have asked if the same could happen to me. I have always told them not to worry, but the truth is I carry a “faulty” gene.”

Jolie goes on to give a step-by-step description of the treatment process – from surgery to remove the breast tissue to reconstructive surgery and implants.

While she kept silent for the duration of the procedure, she explained that she was choosing to share her story now in an effort to inspire other women affected by the disease.

“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.”

Breast cancer kills an estimated 458,000 people each year, according to the World Health Organization.

While the decision to undergo a preventative mastectomy would be difficult for anyone, it’s almost impossible to imagine how challenging it must have been for a woman who has (at least partly) made her living on her looks.

But Jolie dismisses those concerns, writing “I do not feel any less of a woman. I feel empowered that I made a strong choice that in no way diminishes my femininity.” She also gave thanks for the love and support of Pitt, who was at her side for “every minute of the surgeries.”

This story struck a deeply personal note for me, because I’ve often considered getting tested for the BRCA1 and BRCA2 gene. We have a long family history of cancer – I lost my maternal aunt and my mother to the disease. My mom died just when we were getting to the good part, just when I was outgrowing my rebellious teen years and we were finding our way back to each other.

I think that if I knew that I was giving myself a better chance of being there for my own child’s high school graduation, wedding, the birth of my first grandchild, I would do it without hesitation.

What do you think? Have you ever considered being tested for the BRCA genes? Would you ever undergo a preventative mastectomy?