Compared with conventional insemination, intracytoplasmic sperm injection provides no benefit in cases of nonmale factor infertility as evidenced by comparable euploidy rate

Abstract

To evaluate if differences in euploidy rates exist between intracytoplasmic sperm injection (ICSI) and conventional insemination (CI) in non-male factor infertility cases. Retrospective cohort study. Single, academically affiliated infertility center in the U.S. A total of 3,554 patients who underwent in-vitro fertilization (IVF) cycles from January 2014 to December 2021. All cycles that had pre-implantation testing for aneuploidy (PGT-A) performed by trophectoderm biopsy and had a post preparation sperm concentration >4 million total motile sperm per milliliter were included. The primary outcome was embryo euploidy rate per embryo biopsied in the ICSI versus CI group. Secondary outcomes included fertilization rate and number of embryos biopsied. Generalized estimating equations with a Poisson distribution was used to estimate the euploid rate ratio (with total embryos biopsied as an offset), while accounting for multiple retrievals per patient. To adjust for confounding, a propensity score model was fit for ICSI using 14 baseline female and male characteristics. Oocytes retrieved and number of embryos biopsied were similar in both groups, while fertilization rate per oocyte retrieved was significantly lower with ICSI (0.64 vs 0.66, p=0.04). The proportion of euploid embryos in the ICSI group was significantly lower when compared to CI (0.47 vs 0.52), with a euploid rate ratio of 0.89 (p<0.001). Interestingly, when accounting for variation in PGT reference laboratories over the study time period, adjusting for date of procedure did not change the relationship between ICSI and euploid rate (RR=0.89, p<0.001); however, after adjusting for PGT reference laboratory, the relationship between ICSI and euploid rate was no longer significant (RR=0.97, p=0.07). In the setting of non-male factor infertility, ICSI resulted in a lower fertilization rate and an 11% lower embryo euploid rate compared to CI. Although the data is not statistically significant when adjusted for PGT reference laboratory, we can still conclude that ICSI does not provide any benefit. This data supports the recommendation that CI should be the preferred methodology of fertilization in non-male factor infertility cases.