Interval of injections of intramuscular depot medroxyprogesterone acetate in the long-term treatment of endometriosis-associated pain: a randomized comparative trial.

AIM To determine the optimal interval of injections of intramuscular depot medroxyprogesterone acetate 150 mg in the long-term treatment of endometriosis-associated pain. METHOD 112 patients with symptomatic endometriosis were randomized to receive either injections every month for 6 months, then every 3 months for a total of 15 months or injections every 3 months for 15 months. The primary outcome measure was patients' satisfaction. RESULT At months 3, 6, 9, 12 and 15 of the treatment phase, there was no statistically significant difference of percentages of patients with satisfaction between the two regimens (85.7 vs. 76.8%, 76.8 vs. 73.2%, 66.1 vs. 58.9%, 60.7 vs. 55.4%, 60.7 vs. 55.4%, respectively). CONCLUSION The optimal interval of injections of depot medroxyprogesterone acetate 150 mg is every 3 months.