Sept. 15, 2003 -- Early this month the FDA approved an extended-cycle birth control pill that reduces periods to just four per year. Now comes word that using the pill to eliminate menstrual cycles altogether can be an effective endometriosis treatment.
Researchers from Italy's University of Milano used continuous low-dose oral contraceptives to treat 50 women who had undergone unsuccessful surgery followed by cyclic oral contraception to relieve pelvic pain caused by endometriosis. More than half to two thirds of the women reported being satisfied with the continuous oral contraception for pain relief, and 12% also reported relief from menstrual migraine headaches.
In addition to relieving pain symptoms, the treatment just might prevent the endometriosis from getting worse. Ultrasound imaging showed no evidence of new cysts or growth of existing cysts (indicative of endometriosis on the ovary) while the women were taking continuous contraception -- supporting the hypothesis that endometriosis-associated cyst development may be driven by ovulation.
Fewer Periods, Less Pain?
More than 5 million women in the United States have endometriosis, and some suffer from periodic pain so severe that they find it difficult to function during certain days of the month. The condition occurs when the tissue that lines the uterus also grows outside of it. Like the tissue within the uterus, misplaced endometrial tissue sheds at the end of every menstrual cycle. But unlike the uterine lining, which is expelled during menstruation, blood from the misplaced tissue remains trapped. Surrounding tissue often becomes inflamed, and over time scar tissue and cysts form.
So it stands to reason that the fewer periods a woman with endometriosis has, the less likely she is to experience cycle-related pain.
All the women in the Italian study had been treated with oral contraceptive given in the traditional way -- meaning they took active hormone for 21 days each month and placebo pills for seven resulting in a monthly period -- and all reported recurrent moderate to severe pain despite taking the cyclic pill after surgery for endometriosis.
They were placed on the continuous hormone treatment for two years, during which time they were examined every six months and asked to rate their pain severity. At each six-month visit they were also given the option of proceeding with the continuous pill, switching back to the three-week cyclic pill, or discontinuing treatment altogether.
The most frequently reported side effects were spotting, seen in 36% of patients, and breakthrough bleeding, seen in 26%. At the final follow-up evaluation, 80% of the women were either very satisfied or satisfied with the treatment and 16% were dissatisfied.
"Continuous use of an oral contraceptive can be considered an effective, nonsurgical treatment alternative in women with symptomatic endometriosis and menstruation-related pain symptoms who do not want [to become pregnant]," researcher Paolo Vercellini, MD, and colleagues wrote in the September issue of the journal Fertility and Sterility.
Not a New Idea
Women's health expert David F. Archer, MD, professor of obstetrics and gynecology at Eastern Virginia Medical School, tells WebMD that the Italian study is one of the first to examine continuous oral contraception for the management of pelvic pain caused by endometriosis, even though the treatment has been around for years.
"I think a lot of physicians in the United States have used treatments similar to this," he says. "Women who have moderate to severe pain, like those in this study, often end up having hysterectomies and both ovaries removed at relatively early ages. Certainly this treatment offers an alternative to hysterectomy for many of these women."
But Archer says the Italian study does little to convince him that continuous suppression of ovulation with birth control pills can "cure" endometriosis. And he questions the design of the study, which did not include a comparison group of women either taking placebo treatments or oral contraceptives on the traditional 21-day schedule.
"It is hard to draw firm conclusions from this study," he says. "But for women not seeking pregnancy with moderate to severe pelvic pain, continuous oral contraceptive use appears to be a useful adjunct to existing endometriosis treatments."