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Obstetrics & Gynecology:
Original Research

Menstrual Reduction With Extended Use of Combination Oral Contraceptive Pills: Randomized Controlled Trial

Miller, Leslie MD; Notter, Katherine M. MD

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OBJECTIVE: To compare a traditional 28‐day cycle to an extended 49‐day cycle of the 30 μg ethinyl estradiol (E2)/300 μg norgestrel monophasic birth control pill regimen.

METHODS: Ninety subjects randomized to either 28‐day cycles with 21 active pills or 49‐day cycles with 42 active pills for a prospective open label trial over four 84‐day reference periods or trimesters. Bleeding, pill taking, and symptom diaries were completed. The sample size with 80% power to detect a 40% reduction in bleeding days required 24 subjects in each arm.

RESULTS: Of the 90 women, 24 subjects (54.5%) on the 28‐day cycle and 29 (63%) on the 49‐day cycle completed the entire study (P = .41). There were no statistically significant differences between the two groups in demographics or continuation rates. There was a significant reduction in bleeding days in the experimental arm beginning in the first trimester (28‐day = 10.9, 49‐day = 6.4 mean days of bleeding, P < .001) and continuing to the fourth trimester (28‐day = 11.3, 49‐day = 5.8 mean days, P = .005). The number of spotting days was similar between both schedules in the first trimester (28‐day = 4.8, 49‐day = 3.7 mean days, P = .24) and continued into the fourth trimester (28‐day = 3.4, 49‐day = 2.9 mean days, P = .30). Annual expenditure for hygiene products was significantly less for extended use subjects (28‐day = $41.45, 49‐day = $17.54 spent, P < .001).

CONCLUSION: Extension of the 28‐day oral contraceptive (OC) cycle to a 49‐day cycle resulted in fewer bleeding days and no increase in mean spotting days or bleeding episodes.

© 2001 by The American College of Obstetricians and Gynecologists.



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