The impact of embryo quality on singleton birthweight in vitrified-thawed single blastocyst transfer cycles (original) (raw)

STUDY QUESTION Does the quality of a single transferred blastocyst affect singleton birthweight in frozen-embryo transfer (FET) cycles? SUMMARY ANSWER The transfer of a poor-quality blastocyst was associated with lower mean birthweight and gestation-adjusted birthweight (Z-scores) when compared with the transfer of an excellent-quality blastocyst during FET cycles. WHAT IS KNOWN ALREADY Embryo quality is a strong predictor of IVF success rates. However, very few studies have examined the effect of embryo quality on singleton birthweight. STUDY DESIGN, SIZE, DURATION This retrospective study involved singleton live births born to women undergoing frozen-thawed single blastocyst transfers during the period from January 2010 to December 2017 at a tertiary care centre. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 1207 women who fulfilled the inclusion criteria were included and were grouped into four groups depending on the blastocyst quality: excellent, good, average and poor. T...