Reproductive Genetics Laboratory May Impact Euploid Blastocyst and Live Birth Rates: a Comparison of 4 National Laboratories' PGT-A Results from Vitrified Donor Oocytes

Objective: To evaluate potential variation in the euploid blastocyst rate and live birth rate (LBR) per single frozen euploid blastocyst transfer, among 4 unique United States reproductive genetics laboratories. Analyses were limited to blastocysts derived from vitrified donor oocytes, to minimize variation in oocyte quality.

Design: Retrospective cohort study from 2016 to 2020.

Setting: Donor Egg Bank Database.

Patient(s): Patients undergoing in vitro fertilization with donor oocytes. We excluded patients with uterine factor, male factor, or surgically extracted sperm. Only healthy women <34 years old were accepted as oocyte donors.

Intervention(s): Next generation sequencing platforms for chromosomal analysis MAIN OUTCOME MEASURE(S): Euploid blastocyst rate and LBR per euploid transfer. Secondary outcomes included the rate of aneuploidy, mosaic calls, biochemical pregnancy loss, and miscarriage rate.

Result(s): A total of 2,633 embryos were included. Four laboratories had >200 embryos tested. Euploid blastocyst rate was significantly higher in laboratory A (73.6%) vs. B (63.3%), C (60.9%), and D (52.3%). Mosaic rate was significantly lower for Laboratories B (2.8%) and C (5.5%) vs. Laboratories A (9.9%) and D (11.5). The LBR was significantly higher in laboratory A (58.73%) vs. laboratory D (47.3%). There were no significant differences in the implantation or miscarriage rate among laboratories.

Conclusion(s): In this large study, controlling for oocyte quality, some preimplantation genetic testing for aneuploidy (PGT-A) laboratories report a significantly higher euploid blastocyst rate with concurrent higher LBR. This type of comparison is important as it provides insight into the role of the PGT-A process in outcomes. Further research is needed to evaluate the differences in laboratory techniques and bioinformatic algorithms accounting for variable outcomes across PGT-A laboratories.