#141 : Enhanced Luteal Support Following IVF/ICSI for Women with Two or More Good-Quality Embryo Transfer Failures Using Both Subcutaneous and Vaginal Progesterone: A Retrospective Cohort Study

Abstract

Background and Aims: Utilizing progesterone to support the luteal phase (LP) in in vitro fertilization is a well-established practice. Subcutaneous progesterone (SC-P) administration has shown pregnancy rates comparable to vaginal progesterone (Vag-P). However, data are not available regarding the efficacy of combining SC-P with Vag-P for women with multiple good-quality embryo transfer (ET) failures. Therefore, this study aims to evaluate the effectiveness of adding SC-P to Vag-P in women who had not conceived following two or more good-quality ETs. Method: A retrospective cohort analysis of data collected from a university-affiliated fertility centre in the UK between January 2020 to May 2022. A total of 224 embryo transfer cycles, including 65 fresh embryo transfer (fresh-ET) cycles and 159 frozen embryo transfer (FET) cycles in women who had not conceived or experienced miscarriages following two or more good-quality ETs, were analysed. The luteal support protocol was either micronized Vag-P (gel 90mg daily in fresh-ET cycles or pessaries 800mg daily in FET cycles) plus SC-P 25mg once daily (enhanced group) or Vag-P alone (control group). The pregnancy outcomes between the two groups were compared. Clinical pregnancy rates (CPR) represented the primary outcome. Results: In fresh-ET cycles, the enhanced group resulted in higher CPR than the control group. However, statistical significance was not achieved (40% (14/35) vs. 30% (9/30), p=0.40; multivariate analysis adjusted OR 1.54, 95% CI 0.48–4.93, p=0.468). In FET cycles, CPRs were comparable between the enhanced group and the control group (32.3% (21/65) vs. 31.9 % (30/94), p=0.958; multivariate analysis adjusted OR 0.98, 95% CI 0.47–2.03, p=0.953). In both fresh and frozen cycles, no significant difference was observed regarding the positive pregnancy test and miscarriage rates between the two groups. Conclusion: Adding SC-P to Vag-P did not improve pregnancy outcomes for women who had not conceived following two or more good-quality ETs.