Borgstrøm MB, Grøndahl ML, Klausen TW, et al. - Via this multicenter historical cohort study, researchers sought to determine whether the age of women undergoing assisted reproductive technology treatment associates with stage, morphology, and implantation of the competent blastocyst. From 16 private and university-based facilities, they assessed 7,246 women who underwent controlled ovarian stimulation (COS) or frozen-thawed embryo transfer (FET) with a single blastocyst transfer resulting in singleton pregnancy between 2014 and 2018. Findings revealed that age of the woman influences initial human chorionic gonadotrophin [hCG] rise, with an identical pattern for hCG values in COS and FET treatments. The competent blastocyst in COS had a reduced stage with increasing women’s age.