PMDD is characterized by cyclical mood, behavioral and physical symptoms that can be debilitating in some women. The cause of PMDD is unknown, "although it is clear that changes in steroid hormone levels constitute a trigger for symptom production," said Kimberly Yonkers, M.D., associate professor in the Departments of Psychiatry and Epidemiology and Public Health and lead author of the study. She said symptoms are diminished by suppressing ovarian activity and can be provoked by hormones given to women who are no longer menstruating.
The multi-center, double-blind, randomized clinical trial included 450 women ages 18 to 40 from 64 medical centers across the country with symptoms of PMDD and who were given either the oral contraceptive or a placebo. Women who were given the oral contraceptive had significantly greater improvement (48.4 percent compared to 36.1 percent of women on placebo) in productivity, enjoyment of hobbies, social activities, and interpersonal relationships, and experienced greater symptom reduction. Forty-four women from both groups withdrew from the study due to adverse effects such as nausea and intermenstrual bleeding.
The low dose oral contraceptive contains drospirenone, a new progestin, and ethinyl estradiol. It was administered for 24 days followed by four days of inactive pills, which is different than traditional dosing regimens that have a regimen of seven days of inactive pills. The new regimen is designed for greater ovarian suppression and a more stable hormonal environment. The women were evaluated over the course of two menstrual cycles.
Yonkers said the results show the contraceptive is roughly as effective as serotonin reuptake inhibitors (SSRIs), which are commonly used as anti-depressants. "It's not necessarily better, but for women who are seeking contraception in addition to control of PMDD, this would be more efficient because they could take one treatment," she said.
Obstetrics & Gynecology 106: 492-503 (September 2005)