Purpose: This multicenter, double-blind, placebo-controlled crossover study evaluated the efficacy of a new oral contraceptive (OC) formulation containing drospirenone 3 mg and ethinyl estradiol (EE) 20 mug in treating symptoms of premenstrual dysphoric disorder (PMDD).
Method: The OC formulation or placebo was administered for 24 days in a 28-day cycle (24/4), rather than the usual 21-day active treatment, 7-day inert-pill regimen. Participants (N=64) were randomized to either study treatment for three cycles and then after a washout period of one treatment-free cycle switched to the alternate treatment.
Results: The mean decrease from baseline for total Daily Record of Severity of Problems (DRSP) scores while using drospirenone/EE was significantly greater than for placebo (-12.47, 95% CI=-18.28, -6.66; p<.001). A positive response (i.e., a score of 1 or 2 in the Clinical Global Impressions-Improvement scale) occurred in 61.7% and 31.8% of subjects while taking drospirenone/EE and placebo, respectively (p=.009).
Conclusion: Drospirenone/EE, given in a 24/4 regimen, was superior to placebo for improving symptoms associated with PMDD.