COMPARISON OF FOUR NATIONAL REPRODUCTIVE GENETICS LAB PGT-A Results FROM VITRIFIED DONOR EGGS

Abstract

Objective: Given the variation in PGT‐A protocols and bioinformatic analyses between genetic testing labs, we assessed for variation in the euploid blastocyst rate (EBR) between four US labs, using donor oocytes to best control for variations in egg quality and age. Materials and Methods: Retrospective cohort study from 2016‐2019 using the Donor Egg Bank USA (DEB). DEB is a consortium of practices across the country, the PGT‐A lab chosen is a practice specific decision. We excluded patients with uterine factor, male factor or surgically extracted sperm. Only healthy women under 34 are accepted as donors. Primary outcome was EBR. Secondary outcomes included Aneuploid, Mosaic, Ongoing Pregnancy rate (OPR), Chemical pregnancy and Miscarriage rate. Outcomes were compared with X2. Results: 2,633 embryos were included. Four labs had > 200 embryos tested. EBR was significantly higher in Lab A (73.6%) vs B (63.3%), C (60.9%), and D (52.3%), p= <0.001. Mosaic rate was significantly different between labs Lab B (2.8%) and C (5.5%) vs Labs A (9.9%) and D (11.5%), p= <0.001. OPR/LBR was higher in Lab A (57.3%) vs Labs B (51.4%), D (47.2%) and C (47%), p= 0.2. Implantation rate and miscarriage rates were the same. Conclusions: In this large study, controlling for oocyte quality, some PGT‐A labs report a significantly higher EBR. This type of comparison is important as it provides insight into the role of the PGT‐A lab in outcomes. Further research is needed to evaluate the differences in lab techniques and bioinformatic algorithms accounting for variable EBR across PGTA labs. It is surprising that less than 60% of blasts from donor oocytes are suitable for transfer.1 Impact Statement: Analysis of this large sample of embryos generated with donor oocytes suggests that the genetics lab itself may also be an important factor in EBR and pregnancy outcomes. More information is needed to compare the bioinformatics pipelines of different PGT‐A labs to enable physicians and patients to make better‐informed decisions. [Formula presented] References: [1] Forman EJ, et al. In vitro fertilization with single euploid blastocyst transfer: a randomized controlled trial. Fertil Steril. 2013 Jul;100(1):100‐7.e1. Epub 2013 Mar 30. PMID: 23548942.