P-330 Is 17 alpha hydroxyprogesterone caproate an adequate alternative to improve reproductive outcomes in artificially prepared frozen embryo transfer cycles (FET)?

Abstract Study question Is 17 alpha-hydroxyprogesterone caproate an adequate option to improve reproductive outcomes in patients with low serum progesterone (P4) level the day of frozen embryo transfer? Summary answer Patients P4<10ng/ml may benefit addition intramuscular 17alpha-hydroxyprogesterone injections, and have similar ongoing pregnancy rates than P4≥10ng/ml. What is known already Indications cryopreservation expanded last years. Recently published papers highlight that levels before transfers decrease live birth increase miscarriage rates, even cases euploid embryos transfers. Other studies a beneficial effect daily subcutaneous injections around time In Argentina has been available since October 2022, not before. synthetic progestin used for luteal phase support approved prevention preterm birth. design, size, duration This prospective cohort study was performed between May 2021 August 2022 114 undergoing 138 FET cycles after artificial endometrial preparation estradiol valerate 4mg micronized vaginal 200mg, three times daily. Participants/materials, setting, methods <50 years old triple-layer endometrium ≥7mm underwent transfer. Progesterone measured immediately Group 1 (N = 47): P4>10ng/ml; 2 46): transfer; 3 without alpha-hydroxyprogesterone. Primary endpoint compare rate beyond week 12 groups. Secondary endpoints were rate. Main results role chance Parameters comparable groups terms age, body mass index, estradiol, P4 at beginning number transferred. Ongoing was: 38.3% (18/47); 39.1% (18/46); 28.3% (13/46) (p 0,337). Pregnancy 48,9% (23/47); 50% (23/46); (23/46) (p>0,05). Miscarriage 21.73% (5/23), 26.1% (6/23) 43.47% (10/23) 0,208). Although there no significant differences groups, both, 2, had higher lower group 3. probably due limited sample size. Limitations, reasons caution The main limitation our size fact most genetically evaluated being transferred, which would eliminate variable could interfere obtained. Only studied. Wider implications findings exogenous on transfer levels, simple safe strategy individualize when other form administration available. Trial registration NOT APPLICABLE