Objective: To assess whether a low- dose oral contraceptive (OC) is more effective than placebo treatment for dysmenorrhea pain in adolescents. Methods: This was a randomized, doubleblind, placebo- controlled clinical trial of 76 healthy adolescents aged 19 years or younger reporting moderate or severe dysmenorrhea. Subjects were randomly allocated to receive either an OC (ethinyl estradiol [E2] 20 μ g and levonorgestrel 100 μ g) or a matching placebo for 3 months. Parsicipants used their usual pain medications as needed during the trial. The main outcome measure was score on the Moos Menstrual Distress Questionnaire (pain subscale) for the third menstrual cycle on treatment. Secondary outcomes included pain intensity (rated 0 to 10), days of any pain, days of severe pain, hours of pain on worst day, and use of pain medications. Results: The mean Moos Menstrual Distress Questionnaire pain score was lower (less pain) in the OC group than the placebo group (3.1, standard deviation 3.2 compared with 5.8, standard deviation 4.5, P = .004, 95% confidence interval for the difference between means 0.88- 4.53). By cycle 3, OC users rated their worst pain as less (mean pain rating 3.7 compared with 5.4, P = .02) and used fewer pain medications than placebo users (mean pain pills used 1.3 compared with 3.7, P = .05). By cycle 3, OC users reported fewer days of any pain, fewer days of severe pain, and fewer hours of pain on the worst pain day than placebo users; however, these differences did not reach statistical significance. Conclusions: Among adolescents, a low- dose oral contraceptive relieved dysmenorrhea- associated pain more effectively than placebo. Objective: To assess whether a low-dose oral contraceptive (OC) is more effective than placebo treatment for dysmenorrhea pain in adolescents. Methods: This was a randomized, doubleblind, placebo-controlled clinical trial of 76 healthy adolescents aged 19 years or younger reporting moderate or severe dysmenorrhea. Subjects were randomly allocated to receive either an OC (ethinyl estradiol [E2] 20 μg and levonorgestrel 100 μg) or a matching placebo for 3 months. Parsicipants used their usual pain medications as needed during the trial. The main outcomes measure was score on the Moos Menstrual Distress Questionnaire (pain subscale) for the third menstrual cycle on treatment. Secondary outcomes included pain intensity (rated 0 to 10), days of any pain, days of severe pain, hours of pain on worst day, and use of pain medications. Results: The mean Moos Menstrual Distress Questionnaire pain score was lower (less pain) in the OC group than the placebo group (3.1, standard deviation 3.2 compared with 5.8, standard deviation 4.5, P = .004, 95% confidence interval for the difference between means 0.88- 4.53). By cycle 3, OC users rated their worst pain as less (mean pain rating 3.7 compared with 5.4, P = .02) and used fewer pain medications than placebo users (mean pain pills used 1.3 compared with 3.7, P = .05). By cycle 3, OC users reported fewer days of any pain, fewer days of severe pain, and fewer hours of pain on the worst pain day than placebo users; however, these differences did not reach statistical significance. Conclusions: Among adolescents, a low- dose oral contraceptive relieved dysmenorrhea- associated pain more than than placebo.