P-163 Three-year follow-up of babies born derived from mono-pronuclear zygotes

Abstract Study question Are neonatal outcomes normal up to 3 years of ages from the transfer blastocysts derived mono-pronuclear(1PN) zygotes? Summary answer There was no effect on growth in babies born 1PN-implanted blastocysts. What is known already In human ART, 1PN zygotes are observed at low rates. We have previously reported that 80.7% had a biparental chromosome using Live-Cell imaging technique, and some these developed blastocyst stage (Tokoro et al. ASRM 2013). Furthermore, we can result viable pregnancy healthy live birth (Tsuji 2020), there 18-months ESHRE 2021). However, information long-term prognosis from1PN-zygotes. design, size, duration This retrospective study which included 86 cases where after single embryo zygote. The incidence defects, weight were recorded as well physical development survey 19 children who responded 3-years follow-up survey. time period 108 months (January 2013 December Participants/materials, setting, methods Patients seeking fertility treatment an established private IVF clinic. compared weight, old height with data control, 2PN group. Statistical significance determined t-test (level P < 0.05). Main results role chance defects embryo-derived infants 1.2% (1/86). average boys group 3147.6+/-408.7 g, not significantly different 3070.5+/-479.5 g girls, 3048.1+/-510.7 group, (2966.2+/-462.7 g). 18-months, 81.3+/-2.5 cm vs 80.9+/-3.4 for boys; 79.5+/-2.2 79.5+/-3.0 girls groups, respectively. body weights groups 11.0+/-1.2 kg 10.8+/-1.1 9.8+/-1.0 10.2+/-1.1 3-years, 95.2+/-3.1 93.8+/-4.5 91.5+/-2.9 92.5+/-4.9 14.7+/-1.2 14.1+/-1.5 13.2+/-1.9 13.6+/-1.5 significant difference up-to Limitations, reasons caution 1PN- develop resulting births limited transfer. Wider implications findings congenital anomalies Japan around 1.7 2%, similar Also, 2PN. These reassuring clinical utility embryos. Trial registration number applicable