Oral contraceptives, first approved by the U.S. Food and Drug Administration (FDA) in 1960, were originally meant to prevent unwanted pregnancies. In the standard regimen, women take the medication for 21 days, followed by a week of medication-free pills, when menstruation occurs. Many women experience other advantages of oral contraceptives, including less bloating; milder cramps; reduced symptoms of premenstrual syndrome; and relief from migraines, acne, and endometriosis. In fact, physicians often prescribe oral contraceptives to treat such conditions.
In 2003 Barr Pharmaceuticals introduced its Seasonale birth control pill, which reduces the frequency of periods to just four per year. Now Wyeth Pharmaceuticals is seeking FDA approval for Lybrel, another combination contraceptive taken daily but with no medication-free pills, which means no withdrawal bleeding. Lybrel contains lower doses of two hormones-levonorgestrel 90 micrograms and ethinyl estradiol 20 micrograms-than do traditional oral contraceptives, and its safety and effectiveness have so far been found to be comparable.
If approved, Lybrel will be the first oral contraceptive designed to offer women continuous menstrual suppression. This is not a new idea, however, according to Susan Wysocki, president and chief executive officer of the National Association of Nurse Practitioners in Women's Health (http://www.npwh.org) in Washington, DC. Since 1975, Wysocki has prescribed standard birth control pills for extended menstrual suppression to treat endo-metriosis and menstrual cycle problems or to prevent inconvenient bleeding during a honeymoon or vacation. Women simply ignore the medication-free week and take the full-strength pill daily. Moreover, Wysocki adds, many NPs and female physicians use this regimen themselves "because we believe it's safe." (Extended cycling also can be accomplished with transdermal patches or vaginal rings.)
However, Margaret Freda, a professor of obstetrics and gynecology and women's health at Albert Einstein College of Medicine in New York City and editor of the American Journal of Maternal/Child Nursing, is more cautious. "The jury is still out on total menstrual suppression," she says, until long-term studies of its safety are done. Although oral contraceptives have proven safe in general, she adds, "we have no such data for this new regimen."
A review in the October 2005 issue of Current Opinions in Obstetrics and Gynecology (COOG) notes that extended menstrual suppression-often prescribed for adolescents with menstrual disorders and increasingly popular among younger women-has thus far been found to be well tolerated, not to cause adverse endometrial changes, and to increase contraceptive effectiveness, since the transition between pill cycles is the prime time for contraceptive failure. However, breakthrough bleeding is more common during the first few months of extended cycles than when oral contraceptives are used in the standard regimen.
The COOG review points to the need for long-term clinical trials of menstrual suppression, especially regarding the risks of cancer, cardiovascular disease, and impaired fertility, as well as investigations of its effect on bone density, particularly in teenage patients. The review authors also raise the concern that menstrual suppression may convey a message to younger women that menstruation is unhealthy or harmful.
According to a survey by the Association of Reproductive Health Professionals in Washington, DC, 40% of women would choose not to have periods at all, although many women also express concerns about financial costs and possible adverse effects of using oral contraceptives for extended menstrual suppression. (Read the survey at http://www.arhp.org/2005menstruationsurvey.)
Carol Potera