Clinical, Obstetrical, and Neonatal Outcomes after Single Euploid Frozen-Thawed Blastocyst Transfer with Subcutaneous Versus Intramuscular Progesterone Administration

Abstract

Objective: To assess whether subcutaneous progesterone (SC-P) is non-inferior to intramuscular progesterone (IM-P) in terms of live birth rates and perinatal and obstetrical outcomes following single euploid embryo transfer.

Study Design: This retrospective cohort study involved 350 participants who underwent single euploid blastocyst frozen embryo transfer (FET), comprising 219 recipients of intramuscular progesterone (IM-P) and 131 recipients   of   subcutaneous   progesterone (SC-P).   All   embryo   transfers   were   conducted   within   a hormone   replacement   therapy (HRT) protocol   utilizing   incremental   oral   estradiol   valerate.   Upon reaching   an   endometrial   thickness   exceeding   7mm, patients   received   either   intramuscular progesterone (50   mg) or subcutaneous   progesterone (50 mg) ten   to thirteen   days   after priming. The primary outcome measures included live birth rates, as well as obstetrical and perinatal outcomes.

Results: The clinical pregnancy rates were comparable between the intramuscular progesterone (IM-P) group (61.6%; 135/219) and the subcutaneous progesterone (SC-P) group (69.5%; 91/131, p=0.139). The live birth rates exhibited no significant difference between the IM-P group (49.8%; 109/219) and the SC-P group (58%; 76/131, p=,135). Miscarriage rates were also comparable, with 6.3% (22/135) in the IM-P group and 15.4% (14/91) in the SC-P group (p=0.854). Furthermore, there were no statistically significant variances observed between the IM-P and SC-P groups regarding the median gestational age of all live-born neonates (38 weeks in both groups; p=0.183),   birth   weights   (median   of   3205g   in   the   IM-P   group   versus   3335g   in   the   SC-P   group; p=0.073), and the incidence of pregnancy-induced hypertension (4.6% in the IM-P group versus 5.3% in the SC-P group; p=0.833).

Conclusion: The   study   results   offer   clinical   evidence   indicating   that   subcutaneous   progesterone (SC-P) demonstrates   comparable   efficacy   in   achieving   live   birth   rates   when   compared   to   intramuscular progesterone (IM-P). Moreover, the findings suggest that SC-P does not pose an elevated risk for adverse obstetrical and perinatal outcomes.