Comparison of pregnancy outcomes for high morphological scoring mosaic vs. low morphological scoring euploid embryos: a retrospective cohort study.

Abstract

Background: Mosaic embryos have been proven to be capable of resulting in live births and have become an option for embryo transfer under certain circumstances. Recent guidelines suggested that embryo morphological scoring should be taken into consideration when selecting mosaic embryos for transfer. Therefore, we introduce a hypothesis that a high morphological scoring mosaic embryo is a better choice compared to a low morphological scoring euploid embryo.

Materials and methods: This retrospective cohort study included 1641 embryo transfer cycles following next-generation sequencing (NGS)-based preimplantation genetic testing for aneuploidy (PGT-A). Participants were categorized into a mosaic group (87 cycles) and an euploid group (1554 cycles) based on the PGT-A results of the transferred embryos. Statistical methods including multivariate logistic regression analysis and propensity score matching (PSM) were employed to compare the pregnancy outcomes between mosaic and euploid embryo transfer cycles.

Results: Multivariate logistic regression analysis showed that the transfer of mosaic embryos was a prognosis for the reducing live birth rate (P = 0.043). Furthermore, when comparing the pregnancy outcomes of the high morphological scoring mosaic embryo transfer group with the low morphological scoring euploid embryo transfer group, no significant differences were observed (P > 0.05). Additionally, no significant differences in pregnancy outcomes were found between both the high morphological score low proportion and segmental mosaic group and the low morphological score euploid group (P > 0.05).

Conclusion: Our study indicated that morphological scoring has reference value when choosing between euploid and mosaic embryo transfers. Specifically, when the morphological score of euploid embryos is poor, mosaic embryos with high morphological scores could be a viable option after comprehensive prenatal consultation.