Does Embryonic Culture Environment Affect Ploidy Rates in ART Cycles: A Single Center Study in UK

Odia, Rabi; Xavier, Vinals-Gonzalez; Heath, Carleen; Saab, Wael; Ozturk, Ozkan; Seshadri, Srividya; Serha, Paul

doi:10.18502/jri.v23i3.10007

Does Embryonic Culture Environment Affect Ploidy Rates in ART Cycles: A Single Center Study in UK

Authors

Rabi Odia

Vinals-Gonzalez Xavier

Carleen Heath

Wael Saab

Ozkan Ozturk

Srividya Seshadri

Paul Serha

The Centre for Reproductive and Genetic Health, London, UK

10.18502/jri.v23i3.10007

Abstract

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. 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). Results: The average age across the groups was 38.7±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. 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.

Keywords

Benchtop incubator

Blastocyst

Euploi

Time lapse incubato

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