P-773 No impact of cleavage-stage or blastocyst-stage embryo biopsy on growth and health in children up to 2 years of age

Abstract Study question Does embryo biopsy for preimplantation genetic testing (PGT) followed by fresh or vitrified-warmed transfer affect children’s health up to 2 years of age? Summary answer Cleavage- blastocyst-stage vitrified-warmed-embryo had neither impact on anthropometry at birth, infancy childhood nor outcomes. What is known already Literature data regarding neonatal outcomes after PGT show mixed results due small sample sizes and/or the heterogeneity in terms (cleavage- blastocyst-stage) and type (fresh frozen-thawed). Even fewer exist beyond infancy, including growth. design, size, duration This single-center cohort-study compared singletons conceived cleavage- either a cycle with non-biopsied between 2014 2018. Pregnancies IVM, oocyte vitrification oocyte/embryo donation were excluded. Eligible living Belgium invited examination 3-6 months years. Anthropometric measurements surgeries, medication use hospitalisations are reported. Participants/materials, setting, methods Birth characteristics available 630 222 children cleavage-stage 1532 embryo. Follow-up 426, 131 662 children, respectively. The following cycles was primary outcome. Other timing vitrification. Subgroup analysis according infertility background additionally performed. Main role chance Regarding biopsy, cleavage blastocyst stage, no differences anthropometrics found cycles, even adjustment neonatal, treatment maternal characteristics. Likewise, (cleavage stage) cycles. (day 3 day 5/6) did not childhood. However, born larger birth than transfer. Weight height gain from early comparable all biopsied groups. Reassuringly, rates major congenital malformations, (severe) developmental problems, hospital admissions, surgical interventions chronic age observed parents an diagnosis showed that parameters different biopsy. Limitations, reasons caution As majority our center performed indication only, number infertile rather limited should therefore be interpreted cautiously. Wider implications findings Our add reassurance does adversely offspring age. particular importance given widespread shift PGT. Trial registration Not applicable