Decrease in Cancer Risk for Pill Users
Study Shows 12% Decrease in Cancer Risk for Women Taking Oral Contraceptives
The Pill and Cancer continued...
The women were followed for an average of 36 years, during which time the University of Aberdeen researchers recorded a 12% reduction in overall cancer risk, based on data from a large subset of the women derived from national cancer registries.
That translates to one fewer case of cancer for every 2,200 women who took the pill for a year, Hannaford tells WebMD.
Specifically, contraceptive pill users had significantly lower rates of colorectal, uterine, and ovarian cancer.
'Benefits Outweigh the Risks'
The researchers reported a 22% increase in overall cancer risk among women who took the pill for eight years or longer, including a 2.7-fold increase in cervical cancers and a fivefold increase in rare central nervous system and pituitary cancers.
They had no explanation for the increase in the latter cancers, but noted that the cervical cancer association has been well documented.
Most of the women in the study took the first generation of birth control pills, which contained much higher doses of hormones than are used in the oral contraceptives available today.
Hannaford says it is not clear if the risks and benefits are the same with the newer, lower-dose pills most women take today, but he suspects they are.
"I think these findings do have relevance for today's users, but I am pushing the boundaries a bit to say this because there isn't a lot of research," he says.
The researchers conclude that for most women who take birth control pills, "the cancer benefits associated with oral contraception outweigh the risks."
American Cancer Society epidemiologist Carmen Rodriquez, MD, does not disagree with the statement.
"We know that there is a small increase in breast cancer risk among women who take oral contraceptives, and this cannot be ignored," she says. "But we also know that oral contraception use lowers the risk of ovarian cancer. Since this cancer is so deadly and since we don't have good ways to screen for it or prevent it, I think it's fair to say that the benefits outweigh the risks."