Efficacy of a selective COX-2 inhibitor for controlling irregular uterine bleeding in DMPA users

Abstract

Purpose This double-blind, placebo-controlled study was conducted to evaluate the efficacy of valdecoxib and placebo for controlling irregular uterine bleeding in depot-medroxyprogesterone acetate (DMPA) users. Method A total of 51 DMPA users were enrolled. All subjects in the study had abnormal bleeding and were randomly divided into two groups. One group totaling 22 received valdecoxib, 40 mg, once a day for 5 days, and placebos were given to another 24 in the same manner; 5 subjects dropped out from the study. Analysis of the number of treatment days required for stopping the bleeding episode, percentage of women whose bleeding was stopped in 7 days, total number of bleeding-free days and length of the bleeding-free interval after the initial treatment was determined in the first and the fourth weeks. Results The percentage of the subjects whose bleeding was stopped during the first week after the initial treatment and the mean value of the bleeding-free days during the 28 days of the follow-up period were significantly higher in the valdecoxib group than in the placebo group (77.3% vs. 33.3%, p<.01; and 17.8 days vs. 11.5 days, p<.05, respectively). The mean duration of treatment days required for stopping the bleeding episode in the valdecoxib-treated group was 1.7 days, and the mean duration of the bleeding-free interval in valdecoxib-treated group was 18.6 days. Conclusion Valdecoxib was more effective than placebo in the short-term control of irregular bleeding in DMPA users. The mechanism of nonsteroidal anti-inflammatory drugs (NSAIDs) for the reduction of endometrial bleeding is likely from COX-2 inhibition.