PGT-A in Screening of Embryos in the Treatment of Unexplained Recurrent Miscarriage

This prospective observational study enrolled all women with uRM who underwent array-comparative genomic hybridization (array-CGH) for PGT-A in the Reproductive Medicine Center of Peking University Third Hospital from 2012 to 2016. If a couple underwent multiple stimulation cycles during the research period, only the first cycle was included. All patients underwent adequate clinical and genetic consultations before undergoing PGT-A, and all voluntarily chose PGT-A after fully understanding its risks and benefits. All patients signed the informed consent document of PGT-A. All included stimulation cycles involved intracytoplasmic sperm injection insemination. After successfully fertilized embryos formed blastocysts on Day 5-7, trophoblasts were biopsied to determine embryonic karyotypes. The blastocysts with normal/balanced test results were cryopreserved, whereas abnormal blastocysts were discarded after notifying the patients. All normal blastocysts from a patient were thawed and transferred singly, and the outcomes of all subsequent frozen-thawed embryo transfer cycles were followed-up until January 2020. Clinical outcomes included the blastocyst formation rate, the proportion of blastocysts with normal karyotypes, and the clinical pregnancy, live birth, and cumulative live birth rates. The factors that affected these clinical outcomes were analyzed to predict outcomes and guide treatment in women with uRM.