Does omitting teratospermia as a selection criterion for ICSI change pregnancy rates?

There is controversy whether teratospermia is associated with poorer IVF outcomes and if ICSI may overcome this deficit. The debate likely lies in study heterogeneity, poor adjustment for confounders, and inter-observer variation in sperm morphology assessment. Given the current literature, a shift in practice was implemented at our center in February 2017, whereby teratospermia was no longer a criterion for ICSI. We hypothesized that, despite decreasing ICSI rates, we would see no change in ART outcomes.

A retrospective study was performed including 1821 couples undergoing IVF/ICSI at a single center from January 2016 to December 2018, divided into cohorts before and after the practice change. The primary outcome of clinical pregnancy and secondary outcomes of fertilization, fertilization failure, good quality blastocyst formation, embryo utilization, positive hCG, and miscarriage rates was compared, adjusting for potential confounders. Subgroup analysis was performed evaluating teratospermia as the only reason for a male factor infertility diagnosis.

Despite a decrease in ICSI rate of 30.3%, we found no significant difference in clinical intrauterine pregnancy rate, with an adjusted relative risk of 0.93 (0.81, 1.07, P = 0.3008). There were no significant differences in other secondary outcomes after multivariate adjustment. Subgroup analysis for those with male factor infertility due to teratospermia showed no difference in outcomes.

This study concurs with the recent data suggesting that employing ICSI solely for teratospermia is unnecessary. This may allow clinics to decrease ICSI rates without sacrificing success rates, leading to lower cost and risk associated with treatment.