en 36415499 <p>Background: The purpose of the current study was to assess whether embryonic culture conditions has an impact on embryo ploidy in a preimplantation genetic testing for aneuploidy (PGT-A) cycle.<br /> Methods: In this retrospective single center cohort study, a total of 1099 blastocysts from 278 PGT-A cycles were analyzed. The generated blastocysts were biopsied on days 5 and 6. Inseminated oocytes were allocated in different incubators (benchtop and time lapse) and assisted zona hatching was performed on day 3 of embryo development to facilitate the biopsy process which was performed on days 5 and 6 (blastocyst stage).<br /> Results: The average age across the groups was 38.7&plusmn;3.6 years and the total number of mature eggs was 2912 which were randomly distributed across both incubators. The euploidy rate obtained from both groups showed a higher proportion of euploid embryos in the TLM incubator (37.03%, 95% CI 31.9-42.1) compared to those cultured in the BT incubator (30.4%, 95% CI 23.1-37.7). Regression analysis showed that female age remains to be the key variable driving euploidy rates (0.85, 95% CI 0.82-0.88) although incubator type could be an important covariable (0.54, 95% CI 0.45-0.59). A subgroup analysis of 74 single euploid embryo transfers showed comparable pregnancy and live birth rates.<br /> Conclusion: This large cohort study demonstrates that uninterrupted controlled culture environment provides increased probability to develop euploid embryo in a PGT-A cycle. However, further evaluation is required to assess how environmental culture conditions at a cellular level could affect epigenetic mechanisms in embryo development and higher aneuploidy rate.</p> Benchtop incubator, Blastocyst, Euploi, Time lapse incubato 169 177 https://www.jri.ir/article/120157 https://www.jri.ir/documents/fullpaper/en/120157.pdf RabiOdiaThe Centre for Reproductive and Genetic Health, London, UKrabiodia@yahoo.co.uk41895Vinals-GonzalezXavierThe Centre for Reproductive and Genetic Health, London, UK112424CarleenHeathThe Centre for Reproductive and Genetic Health, London, UK41897WaelSaabThe Centre for Reproductive and Genetic Health, London, UK112098OzkanOzturkThe Centre for Reproductive and Genetic Health, London, UK112294SrividyaSeshadriThe Centre for Reproductive and Genetic Health, London, UK112100PaulSerhaThe Centre for Reproductive and Genetic Health, London, UK112299