EFFECTS OF SPERM AGE ON EMBRYO PLOIDY IN PGT-A

Abstract

PGT-A is routinely offered to patients undergoing IVF. Advanced maternal age (AMA), defined as ≥35 years, has a known significant effect on embryo ploidy status. The effects of advanced paternal age (APA), defined as ≥40 years, on ploidy have been studied less. This study assesses euploid and mosaic rates of embryos created with donor sperm (DS), non-APA sperm, and APA sperm, stratified by use of donor egg (DE), non-AMA eggs, and AMA eggs. Retrospective analysis. All samples received 5/2018 - 5/2020 were included, except for those sent for PGT-SR or with suspected rearrangements. Samples created with known donor gametes were categorized with their respective age groups. Whole-genome amplification, next generation sequencing, and data analysis was performed using the Ion ReproSeqTM PGS Kit and Ion ReporterTM software (Thermo Fisher Scientific). Results were reported as 1) no abnormal cells detected, 2) abnormal cells detected (with percentages if mosaicism was identified), or 3) did not pass quality control (QC) metrics, leading to embryo categories euploid, aneuploid, mosaic, and QC failure. Results were tallied and chi square analyses were performed to compare euploid and mosaic rates between DS samples and non-APA and APA sperm samples. A total of 23,239 samples from 4,691 cycles were included. Table 1 displays ploidy rates for each group and corresponding chi square p-values. Our data shows that sperm age can have an effect on embryos’ ploidy status, as shown by a significantly higher euploid rate in embryos created with DE and DS compared to those created using DE and either non-APA or APA sperm; this effect was noted even with a small sample size. Amongst embryos created with AMA eggs, DS has less of an effect, demonstrating that egg age is still the primary factor affecting embryo ploidy. Clinicians can use this information when counseling patients on the effects of AMA and APA on embryo ploidy.Tabled 1Table 1. Euploid & Mosaic Rates by GroupEmbryo Categories% Euploidχ2 p-value (Euploid)% Mosaicχ2 p-value (Mosaic)Average Egg Age (years)Average Sperm Age (years)DE + DS97/146-19/146-25.228.266.44%13.01%DE + S<401770/3146p = 0.015581/3146NS25.834.656.26%18.47%DE + S≥401478/2593p = 0.025456/2593NS264657.00%17.59%E<35 + DS265/494-99/494-31.626.353.64%20.04%E<35 + S<402662/4808NS757/4808p = 0.01331.833.755.37%15.74%E<35 + S≥40455/829NS129/829p = 0.03732.146.254.89%15.56%E≥35 + DS396/1145-129/1145-39.427.434.59%11.27%E≥35 + S<402122/5251p = 0.0003646/5251NS37.736.340.41%12.30%E≥35 + S≥401559/4827NS458/4827NS39.445.132.30%9.49%DE: donor egg; DS: donor sperm; S<40: non-APA sperm; S≥40: APA sperm; E<35: non-AMA egg; E≥35: AMA egg; NS: not significant Open table in a new tab