P-519 Is oral dydrogesterone a good alternative to vaginal micronized progesterone for luteal phase support in women receiving oocyte donation?

Abstract

Abstract Study question Does oral dydrogesterone (OD) in luteal phase support (LPS) provide equivalent clinical pregnancy and miscarriage rates as micronized vaginal progesterone (MVP) in oocyte donation recipients? Summary answer No significant difference in clinical pregnancy and miscarriage rates was observed when using OD instead of MVP for LPS in oocyte donation. What is known already Dydrogesterone has a higher bioavailability than MVP due to its high specificity for progesterone receptors allowing the use of lower doses limiting side effects. In addition, because of its route of administration, its tolerance is better. The use of OD for LPS in fresh IVF cycles is now well recognized. However, few data are available on its use in frozen-thawed embryo transfer especially in artificial cycles. In this situation, the lack of corpus luteum leads to a total dependence on exogenous progestogens for implantation and maintenance of the pregnancy. Study design, size, duration A retrospective observational study was performed from prospectively collected data in the ART Department of Lille University Hospital from July 2018 to July 2022. Participants/materials, setting, methods Our study analysed 372 oocyte donation cycles with embryo transfer. Recipients underwent endometrial preparation by hormone replacement treatment (artificial cycles). LPS was provided by weekly intramuscular progesterone (500 mg/2ml) and either OD 40 mg per day or MVP 800 mg per day for 12 weeks if the pregnancy test was positive. The primary endpoint was clinical pregnancy rate. Main results and the role of chance This study compared the outcome of 162 transfers with dydrogesterone + IM progesterone to the outcome of 210 transfers with the MVP + IM progesterone. No significant difference was found between the two groups except for the number of embryos transferred, embryo quality, donor BMI and fresh or frozen status of the embryo. After adjustment for these criteria, our two groups were comparable in clinical pregnancy rates with 36.67% in the MVP group versus 30.25% in the OD group (OR 0.868 [0.529 ; 1.423], p = 0.57), ongoing pregnancy rates (29.05% versus 25.31%, OR 0.993 [0.591; 1.669], p = 0.97), miscarriage rates (7.62% versus 4.94%, OR 0.640 [0.248; 1.650], p = 0.35) and live birth rates (26.67% versus 17.69%, OR 0.727 [0.412; 1.284], p = 0.27). Limitations, reasons for caution The main limitation of this study is the non-randomisation of data between the two treatment groups. Wider implications of the findings Our study suggests that dydrogesterone has a place in our LPS strategies in artificial cycle for frozen embryo transfers or in oocyte donation, especially as this route is often preferred by patients and very well tolerated. Further prospective cohorts or randomized trials could continue to inform clinical practice on LPS. Trial registration number DEC 16-25