Alison B Edelman1, Jeffrey T Jensen2, Sara McCrimmon3, Marci Messerle-Forbes3, Andrea O'Donnell3, Jon D Hennebold2. 1. Department of Obstetrics & Gynecology, Oregon Health & Science University, Portland, Oregon; Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Beaverton, Oregon. Electronic address: edelmana@ohsu.edu. 2. Department of Obstetrics & Gynecology, Oregon Health & Science University, Portland, Oregon; Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Beaverton, Oregon. 3. Department of Obstetrics & Gynecology, Oregon Health & Science University, Portland, Oregon.
Abstract
OBJECTIVE: To determine if a combined oral contraceptive (COC) initiated shortly after ulipristal acetate (UPA) administration interferes with its mechanism of action. STUDY DESIGN: Healthy, reproductive-age women of normal BMI with proven ovulation (serum progesterone >3 ng/ml) were enrolled for three cycles (Cycle 1, UPA only; Cycle 2 washout; Cycle 3 UPA plus COC). During Cycles 1 and 3, subjects were monitored with transvaginal ultrasound and blood sampling for progesterone and LH every other day until a dominant follicle measuring >15 mm was visualized. In both treatment cycles, subjects received UPA (30mg) and were followed daily with similar monitoring for up to 7 days. In Cycle 3 only, subjects initiated a daily COC (0.15 mg levonorgestrel/30 μg ethinyl estradiol) 2 days after UPA. The study had 80% power to detect a 15% difference in the proportion of cycles with at least a 5-day delay in follicle rupture. We assessed follicle rupture as >50% decrease in mean size and adjudicated unclear outcomes with serum hormones. RESULTS: A total of 36 women enrolled and 33 completed all study procedures [age 28.4 years (SD 3.9); BMI 23.4 (SD 2.4)]. Compared to Cycle 1, more subjects demonstrated evidence of follicle rupture in <5 days in Cycle 3 [1/33 (3%) vs. 9/33 (27%), p = .008]. We also included data from 2 subjects who experienced rupture prior to COC dosing in the analysis. CONCLUSION: UPA's effectiveness is significantly reduced by administering COCs 2 days later. IMPLICATIONS: This study demonstrates that UPA's efficacy as an emergency contraceptive is reduced with early exposure to COCs.
OBJECTIVE: To determine if a combined oral contraceptive (COC) initiated shortly after ulipristal acetate (UPA) administration interferes with its mechanism of action. STUDY DESIGN: Healthy, reproductive-age women of normal BMI with proven ovulation (serum progesterone >3 ng/ml) were enrolled for three cycles (Cycle 1, UPA only; Cycle 2 washout; Cycle 3 UPA plus COC). During Cycles 1 and 3, subjects were monitored with transvaginal ultrasound and blood sampling for progesterone and LH every other day until a dominant follicle measuring >15 mm was visualized. In both treatment cycles, subjects received UPA (30mg) and were followed daily with similar monitoring for up to 7 days. In Cycle 3 only, subjects initiated a daily COC (0.15 mg levonorgestrel/30 μg ethinyl estradiol) 2 days after UPA. The study had 80% power to detect a 15% difference in the proportion of cycles with at least a 5-day delay in follicle rupture. We assessed follicle rupture as >50% decrease in mean size and adjudicated unclear outcomes with serum hormones. RESULTS: A total of 36 women enrolled and 33 completed all study procedures [age 28.4 years (SD 3.9); BMI 23.4 (SD 2.4)]. Compared to Cycle 1, more subjects demonstrated evidence of follicle rupture in <5 days in Cycle 3 [1/33 (3%) vs. 9/33 (27%), p = .008]. We also included data from 2 subjects who experienced rupture prior to COC dosing in the analysis. CONCLUSION:UPA's effectiveness is significantly reduced by administering COCs 2 days later. IMPLICATIONS: This study demonstrates that UPA's efficacy as an emergency contraceptive is reduced with early exposure to COCs.
Authors: V Brache; L Cochon; I J M Duijkers; D P Levy; N Kapp; C Monteil; J L Abitbol; C Klipping Journal: Hum Reprod Date: 2015-09-23 Impact factor: 6.918
Authors: Anna F Glasier; Sharon T Cameron; Paul M Fine; Susan J S Logan; William Casale; Jennifer Van Horn; Laszlo Sogor; Diana L Blithe; Bruno Scherrer; Henri Mathe; Amelie Jaspart; Andre Ulmann; Erin Gainer Journal: Lancet Date: 2010-01-29 Impact factor: 79.321
Authors: V Brache; L Cochon; C Jesam; R Maldonado; A M Salvatierra; D P Levy; E Gainer; H B Croxatto Journal: Hum Reprod Date: 2010-07-15 Impact factor: 6.918
Authors: Alison B Edelman; Jon D Hennebold; Kise Bond; Jeong Y Lim; Ganesh Cherala; David F Archer; Jeffrey T Jensen Journal: Obstet Gynecol Date: 2022-06-07 Impact factor: 7.623