P-245 Birth of twenty-seven healthy babies following transfer of fresh and frozen-thawed embryos derived from monopronuclear zygotes: a retrospective study

Abstract Study question What are the neonatal outcomes of fresh/frozen-thawed embryos derived from monopronuclear zygotes (1PN)? Is there any influence method fertilization? Summary answer A total 231 monoembryonic transfers (TF) fresh or frozen/thawed 1PN allows to birth twenty-seven healthy babies. is known already Zygotes were classified 16 18 hours post insemination according extrusion second polar body and number pronuclei (PN). The «normally fertilized» display 2 PN those with 0, 1 more than (> 2PN) considered as abnormal. If some always discarded (>2PN) due increased risk aneuploidy, transfer remains controversial. design, size, duration Our retrospective study included all conventional in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) frozen embryo (FET) cycles performed between january 2018 december 2022. Embryo pregnancy analyzed a first group 781 (731 patients) 167 FET (150 zygote. Only for live rate (LBR). Participants/materials, setting, methods our study. For (n = 2762), outcome was 1234 (1PN) (IVF 648 ICSI 586). Fresh TF 64 cycles. cycles, achieved cases. on day 2, 3 5, rates analyzed. Main results role chance At first, 46% IVF gave rise sufficient quality be transferred (day 5/6). This decreased 33% Blastulation also important (44%) comparison (20%) without signification (p 0.1). patients (32 each group) allowed 7 pregnancies (PR 22%) compared 4 12%). ended deliveries newborns, miscarriages one still ongoing. In group, newborn observed. Secondary, thirty-six obtained non significative difference observed 26%) 16%) respectively 15 6 babies born. Two Limitations, reasons caution main limitation this that it retrospective, single-center relatively small births. Wider implications findings conclusion, we better center policy good developed 26 27 newborns during period Trial registration not applicable