Angelina Jolie had been planning to have her ovaries removed for two years.
The 39-year-old actress underwent a double mastectomy in 2013 after discovering she carries the mutated BRCA1 gene, which meant she had an 87 percent chance of contracting breast cancer and a 50 percent chance of ovarian cancer.
But she and oncologist Dr. Kristin Funk—who performed her mastectomy but not the laparoscopic bilateral salpingo-oophorectomy she had last week—agreed to wait until the "appropriate time" before she underwent the second preventative procedure.
And it was agreed Angelina would have both ovaries and her fallopian tubes removed last week after recent tests revealed markers she could be in the early stages of the disease.
Dr. Funk, from the Pink Lotus Breast Center in California, told Entertainment Tonight: "We had strategized about a way to manage the ovaries with surveillance until she felt it was appropriate in her life to remove them."
Dr. Funk believes the openness of the Tomb Raider star—whose mother, grandmother, and aunt died of cancer—will encourage other celebrities to be open about genetic risk and cancer prevention.
Following Kelly Osbourne's revelation that she too carried the BRCA1 gene, Dr. Funk said: "I think more celebrities and well-known women might find the coming out less daunting not that she has taken away the initial shock and stigma with this revelation.
"I think you'll find more celebrities coming out about it. Hopefully they'll be motivated to take away the stigma, fear and lack of education."
Angelina, who is currently going through the menopause, shared her decision to undergo the surgery in an article in the New York Times newspaper titled "Angelina Jolie Pitt: Diary of a Surgery."
The Hollywood actress revealed she was feeling "feminine and grounded" following the invasive operation.
She said: "A simple blood test had revealed that I carried a mutation in the BRCA1 gene.
"It gave me an estimated 87 percent risk of breast cancer and a 50 percent risk of ovarian cancer. I lost my mother, grandmother and aunt to cancer.
"It is not possible to remove all risk, and the fact is I remain prone to cancer.
"I will look for natural ways to strengthen my immune system. I feel feminine, and grounded in the choices I am making for myself and my family."
Angelina—who has Maddox, 13, Pax, 11 and Zahara 10, Shiloh, eight, and six-year-old twins Knox and Vivienne with her husband Brad Pitt—decided to undergo the procedure for the sake of her children.
She wrote: "I know my children will never have to say, 'Mom died of ovarian cancer.'
"Regardless of the hormone replacements I'm taking, I am now in menopause.
"I will not be able to have any more children, and I expect some physical changes.
"But I feel at ease with whatever will come, not because I am strong but because this is a part of life.
"It is nothing to be feared."