Role of aneuploidy screening in preimplantation genetic testing for monogenic diseases in young women

Objective: To investigate whether aneuploidy screening in preimplantation genetic testing (PGT) for monogenic diseases improves the ongoing pregnancy/live birth rate of single frozen/thawed embryo transfer (FET) cycles in young women. Design: Retrospective cohort study. Setting: Single university-based fertility center. Patient(s): From January 2016 to December 2017, 569 FET cycles were selected for analysis. The aneuploidy screening (AS) group included 131 FET cycles from 105 oocyte retrieval cycles in 98 patients who underwent PGT for monogenic diseases with aneuploidy screening, and the non-AS group included 438 FET cycles from 280 oocyte retrieval cycles in 266 patients who underwent PGT for monogenic diseases without aneuploidy screening. Intervention(s): The patient population was all under the age of 35 years and underwent PGT for monogenic diseases with and without AS. Main Outcome Measure(s): Ongoing pregnancy/live birth rate, live birth rate, implantation rate, and miscarriage rate. Result(s): Aneuploidy screening significantly improved the ongoing pregnancy/live birth rate (61.22% vs. 43.98%), implantation rate (64.29% vs. 50.38%), and live birth rate (53.06% vs. 36.09%) of young women carrying monogenic diseases in the first FET cycles. When adjusted for the parity, number of previous miscarriages, and percentage of infertility, the likelihood of implantation was 1.874 times higher (95% confidence interval 1.126-3.119), and an ongoing pregnancy/live birth was 2.139 times more likely (95% confidence interval 1.295-3.534). In addition, the miscarriage rate was significantly decreased (3.17% vs. 11.94%). In the cumulative pregnancy outcomes, the cumulative ongoing pregnancy/live birth rate both per transfer and per patient were significantly higher in the AS group (62.24% vs. 50.38% and 79.59% vs. 68.80%), but no difference existed after adjusting for the parity, number of previous miscarriage, and percentage of infertility. Nevertheless, aneuploidy screening reduced the time interval from the first ET to the achievement a pregnancy. Conclusion(s): Aneuploidy screening in PGT significantly improved the ongoing pregnancy/live birth rate of young women carrying monogenic diseases in the first FET cycles. ((C) 2019 by American Society for Reproductive Medicine.)