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Short Communication: Conflicting Conclusions in PGT-A: Live Birth Rates per Initiated Cycle or Oocyte Retrieval Show
Isabela M Pasotti1, Claudia Petersen1,2, Laura D Vagnini2,3
1Center for Human Reproduction Prof. Franco Jr, Ribeirão Preto, Brazil.
Objective:
To determine whether studies evaluating preimplantation genetic testing for aneuploidy (PGT-A) reach different conclusions depending on the denominator used to calculate live birth rates.
Methods:
A systematic review of studies published be-tween 2017 and 2025 was conducted using PubMed, Sco-pus, and Google Scholar. Randomized and non-randomized studies comparing IVF/ICSI cycles with and without PGT-A were included. Outcomes were analyzed per initiated cy-cle, oocyte retrieval, or embryo transfer. Relative risks were calculated using a random-effects model.
Results:
Eleven studies were included. No significant difference was observed when live birth rates were ana-lyzed per initiated cycle or oocyte retrieval (RR 1.04, 95% CI 0.91-1.18). However, PGT-A significantly improved live birth rates when analyzed per embryo transfer (RR 1.21, 95% CI 1.05-1.40).
Conclusion:
The apparent benefit of PGT-A depends on the denominator used. Reporting outcomes per embryo transfer introduces selection bias and overestimates treat-ment effectiveness. Clinically meaningful outcomes should be reported per initiated cycle or oocyte retrieval.
