Morphology versus pgt-a: how often does pgt-a impact selection of the embryo for the first tranfer?

Despite multiple randomized controlled trials showing that preimplantation genetic testing for aneuploidy (PGT-A) versus morphology does not lead to improved live birth[1-2], the controversy continues. One touted benefit is that PGT-A improves selection by reducing the number of embryo transfers (ET) needed to reach live birth, but no study measures how it impacts the embryo selected for first ET and if there are particular patient groups that would benefit most from this screening. This study examines how often the best quality embryo selected for first ET is euploid. We compare 2 scenarios, where all cycles undergo fresh ET with the best quality Day 5 embryo, or are freeze-all, with embryos cultured up to Date 6 for a future frozen ET. This was a retrospective analysis of 2,885 autologous IVF cycles at an academic institution from 2016-2022, identifying 10,751 embryos that underwent PGT-A. Cycles yielding all euploid or all aneuploid embryos, plus those with only 1 embryo, were included, whereas cycles yielding multiple embryos of equivalent highest grade were excluded, leaving 2,552 cycles. Assumptions made for quality ranking were: for inner cell mass and trophectoderm: “AA > AB > BA > BB > AC > CA > BC > CB > CC,...”; for developmental stage: “5 > 4 > 3 > 6 > 2 > 1.” Univariate logistic regression was used to assess whether euploidy of the best quality embryo was associated with age and number of embryos. For all cycles, the best quality embryo selected for first ET was euploid 49% of the time. In the youngest group (< 35), 72% of the best quality embryos were euploid. In 35-37 and 38-40, 57% and 41% were euploid, respectively. In the oldest group (> 40), the best quality embryo was euploid 18% of the time. When ≤ 5 embryos were obtained, 43% of the best quality embryos were euploid; 61% with 6-10; 74% with 10-15, 78% with 16+ embryos. The younger the age and the more embryos obtained, the higher the odds that the best quality embryo was euploid (p < 0.01). No significant differences were seen between the two scenarios of fresh ET and freeze-all. PGT-A impacts embryo selection for the first ET in half of IVF cycles but does so differentially by age group and number of embryos. The younger the patient and the more embryos available, the less likely it is for PGT-A to select a poorer quality euploid embryo for the first ET. Table 1 can help guide patient counseling on PGT-A, depending on patient age and anticipated yield of embryos.