Progesterone vaginal ring versus vaginal gel for luteal support with in vitro fertilization: a randomized comparative study.

OBJECTIVE To compare the efficacy and safety of luteal phase support in IVF with a progesterone (P) vaginal ring or gel (VR or VG). DESIGN Prospective, randomized, single-blind, multicenter, phase III clinical trial (ClinicalTrials.gov identifier: NCT00615251). SETTING Nineteen private and three academic high-volume U.S. IVF centers. PATIENT(S) One thousand two hundred ninety-seven infertile patients were randomized to a weekly P VR (n = 646) or a daily P 8% VG (n = 651). INTERVENTION(S) IVF was performed per site-specific protocols. The day after egg retrieval, patients were randomized and began VR or VG therapy, which continued for up to 10 weeks' gestation. MAIN OUTCOME MEASURE(S) Clinical pregnancy rates at 8 and 12 weeks of pregnancy; rates of biochemical pregnancy, live birth, spontaneous abortion, ectopic pregnancy, and cycle cancellation; and safety and tolerability were secondary measures. RESULT(S) Clinical pregnancy rates at 8 and 12 weeks were high and comparable between groups: 48.0% for VR and 47.2% for VG at week 8 and 46.4% (VR) and 45.2% (VG) at week 12. Live-birth rates were 45% (VR) and 43% (VG). Adverse event profiles were similar between groups. CONCLUSION(S) The weekly P VR provided similar pregnancy rates to the daily VG, with no major differences in safety.