Comparable Outcomes Using Oral Dydrogesterone versus Intramuscular Progesterone in Frozen Embryo Transfer: a Retrospective Cohort Study

Abstract Background Optimal intensive luteal support in frozen embryo transfer (FET) cycles in which a corpus luteum is not present has not been determined and several treatment regimens are currently practiced. Previous reports suggest that vaginal progesterone alone is probably insufficient. The use of intramuscular progesterone is considered efficacious but much less tolerable. The objective of this study was to compare a more tolerable regimen using micronized vaginal progesterone (MVP) and oral dydrogesterone versus MVP and intramuscular progesterone (IM) for luteal support. Methods A retrospective study of patients undergoing single blastocyst FET in a tertiary center IVF unit. All patients (n = 100) received oral estradiol in the follicular phase and supplemented with MVP for luteal phase support. One group (n = 50) received additional dydrogesterone (10 mg TID) and the other (n = 50) intramuscular progesterone (100 mg every 3 days). Results The two groups were similar with regard to age; BMI; infertility etiology and duration; and basal hormonal levels. Biochemical pregnancy rates (34% vs 42%, p = 0.54) and clinical pregnancy rates (26% vs. 36%, p = 0.39) were lower in the MVP + oral dydrogesterone group as compared to the MVP + IM progesterone group. Nevertheless, this difference was not statistically significant. Abortion rates were similar (2%) and there were no ectopic pregnancies in both groups. Conclusion This retrospective cohort study demonstrates noninferiority of MVP and oral dydrogesterone as compared to MVP and intramuscular progesterone for luteal support in FET cycles. The better profile of adverse effects and tolerability makes it a suitable protocol for FET.