Preimplantation Genetic Testing for Aneuploidy (PGT-A) on Blastocyst Quality, Vitrification Timing, and IVF Outcomes: A Comparative Study

Research Article

Abstract

Background: Preimplantation genetic testing for aneuploidy (PGT-A) is increasingly applied in assisted reproductive technologies, particularly among individuals with advanced maternal age or a history of recurrent pregnancy loss. By enabling the selection of chromosomally normal embryos, PGT-A may improve implantation rates and pregnancy outcomes following the initial embryo transfer. This study aims to compare ICSI outcomes, blastocyst quality, and vitrification timing between PGT-A and control groups to assess the reproductive outcomes

Methods: A retrospective cohort study was conducted at a MHRT Hospital and Research Center, Hyderabad, involving patients undergoing Intracytoplasmic Sperm Injection (ICSI) cycles between March 2022 and March 2025. The study included 52 PGT-A and 52 control patients, with Baseline characteristics, embryological parameters, blastocyst quality, vitrification timing, and reproductive  outcomes were assessed. The PGT-A group included embryos that underwent aneuploidy testing via trophectoderm biopsy. Blastocyst expansion, inner cell mass (ICM) quality, trophectoderm (TE) grading, and vitrification day were compared between the two groups.

Results: Patients in the PGT-A group were older and had higher rates of primary and female-factor infertility. Hormonal profiles and oocyte retrieval outcomes were comparable between groups. The PGT-A group was older (mean age 36.2 vs. 33.7 years) and had higher proportions of primary infertility (71.15% vs. 59.61%) and female infertility (61.53% vs. 42.3%). Both groups had  more or less similar oocyte retrieval numbers, but the Control group had more prior ICSI cycles. Regarding blastocyst    quality, the PGT-A group exhibited higher proportions of grade 3 and grade 6 blastocysts, with a better ICM grade (B) and TE grade (A). The Control group had a higher proportion of grade 4 blastocysts.  Additionally, more embryos in the Control group were vitrified on Day 5 (76.92% vs. 61.53%), while the PGT-A group showed a higher proportion vitrified on Day 6 (38.46% vs. 23.07%), these differences did not translate into superior clinical outcomes. The cumulative live-birth rate was slightly lower in the PGT-A group (75%) compared to controls (83.69%). Secondary outcomes, including biochemical, clinical, and ongoing pregnancy rates, were also lower in the PGT-A group. Singleton and twin birth weights were marginally reduced in the PGT-A cohort.

Conclusion: PGT-A is associated with higher-quality blastocysts, particularly in terms of ICM and TE grading. It also influences vitrification strategies, with PGT-A embryos more likely to be vitrified on Day 6. These findings suggest that PGT-A may improve embryo quality, potentially enhancing ICSI outcomes, especially in older women or those with recurrent implantation failure. However, further studies are  necessary to refine patient selection criteria and evaluate cost-effectiveness and ethical concerns associated with PGT-A.