Developmental competence and neonatal outcomes of nonpronuclear zygotes following single vitrified-warmed blastocyst transfers using propensity score matching analysis

Abstract

Purpose To investigate developmental competence and neonatal outcomes of nonpronuclear (0PN) zygotes following single vitri ed-warmed blastocyst transfers (VBT).Methods The clinical, laboratorial and neonatal data of 996 patients with ≤38 years who underwent blastocyst culture and single VBT were retrospectively analyzed. The pregnancy and neonatal outcomes of VBT were compared between 0PN and 2PN blastocysts using propensity score matching (PSM). Moreover, Day 3 (D3) embryo development and blastocyst formation were compared between 0PN and 2PN zygotes.ResultsThere were no signi cant differences in clinical pregnancy rate (CPR), live birth rate (LBR) and neonatal outcomes of VBT between the 0PN and 2PN blastocysts irrespectively of whether PSM was used. However, early abortion rate (EAR) was higher in blastocysts from 0PN D3 embryos 10 cells (p 0.05) before PSM. Moreover, the early developmental competence of 0PN zygotes was different from that of 2PN zygotes presenting higher percentages of D3 embryos ≤6 cells (p 0.01) and 10 cells (p 0.01), lower available blastocyst formation rate (ABFR) (p 0.01) and good-quality blastocyst formation rate (GBFR) (p 0.01) in D3 embryos with 4-6 cells. ABFR and GBFR increased with cell number when compared among embryos with 4-6 cells, 7-10 cells and 10 cells, irrespectively of 0PN or 2PN embryos.ConclusionThe early developmental competence of 0PN zygotes was different from that of 2PN zygotes, but did not in uence pregnancy and neonatal outcomes following VBT. ABFR and GBFR increased with cell number, irrespectively of 0PN or 2PN embryos.What does this study add to the clinical work?The early developmental competence of 0PN zygotes was different from that of 2PN zygotes, but did not in uence pregnancy and neonatal outcomes following VBT.The rates of available blastocyst and good-quality blastocyst increased with cell number of D3 embryos, irrespectively of 0PN or 2PN embryos.