Birth control pill lowers long-term risk of ovarian cancer

Oral contraceptives, also called birth-control pills, are widely consumed by millions of women to help prevent pregnancy. Surprisingly, these pills may substantially reduce women's risk of ovarian cancer and continue to protect them even decades after they stop taking it, a new study by British researchers found.

The research, by Oxford University epidemiologists, suggests that the longer a woman uses the oral contraceptive pill, the lower her risk of getting ovarian cancer later in life. The contraceptive pill

"Not only does the pill prevent pregnancy, but in the long term, you actually get less cancer as well," said study’s lead author Valerie Beral, who is also a director of the Cancer Research UK Epidemiology Unit at Oxford University. "It's a nice bonus."

To reach their findings, Beral and colleagues analyzed data from 45 studies in 21 countries, covering 23,257 women with ovarian cancer, of whom 31% were on the pill. They compared the data with a group of 87,303 women without ovarian cancer, of whom 37% were on the pill.

The British researchers found that women taking the pill for 15 years halved their chances of developing ovarian cancer, and that the risk remained low for at least 30 years after they stop taking it.

The researchers noticed that in high-income countries like the UK, where 25% of women aged 16-49 are using the contraceptive pill, women taking oral contraceptives for a decade were less likely to develop ovarian cancer. They found that 10-year use of oral contraceptives reduced the numbers getting ovarian cancer from 12 cases per 1,000 women to eight and their chance of death minimized from seven cases per 1,000 women to five.

Professor Beral said that the pill has already prevented nearly 200,000 women from developing ovarian cancer and has prevented 100,000 deaths from the disease. “More than 100 million women are now taking the pill, so the number of ovarian cancers prevented will rise over the next few decades to about 30,000 per year," he continued.

While the pill protects against ovarian cancer and shown to have protective effects against ovarian, endometrial and colorectal tumors, it instead has been linked to increased risks for breast and cervical cancers.

In November last, a team of international researchers had confirmed that the birth control pills can put the women at a significant risk of developing cervical cancer and other cancers of the womb.

Before this, a European study linked the pills to an increased risk of heart disease, even for women who no longer use the pills, giving shock to those women who are taking these pills for the last many years.

The recent study, published Friday in The Lancet, was paid for by Cancer Research UK and Britain's Medical Research Council.

Introduced in the 1960s, the oral contraceptives are medicines are taken by mouth to help prevent pregnancy. Commonly known as birth control pill, the medicine is now the world's most popular form of contraception used by more than 12 million women in the United States and more than 60 million women worldwide, as per the estimates of U.S. Centers for Disease Control and Prevention.

The contraceptive pill that revolutionized birth control practices uses hormones to suppress ovulation. The pill, typically containing estrogen or progesterone, inhibits ovulation and thereby prevents conception.