Predictive Value of Teratospermia During Initial Sperm Analysis on the Success of Intrauterine Insemination Cycles.

Objective: To evaluate the predictive value of sperm morphology, specifically teratospermia, seen during initial semen analysis on the success of intrauterine insemination (IUI) cycles and pregnancy outcomes.

Methods: A retrospective cohort analysis on patients undergoing IUI at a large US fertility network. Baseline demographic characteristics, primary infertility diagnoses, and pregnancy outcomes were recorded. A total of 27,925 IUI cycles in 16,169 unique patients were analyzed. IUI cycles were grouped by a sperm morphology of 1% (n = 3799), 2% (n = 5506), 3% (n = 4857), or 4% or greater (n = 13,763). The outcome measures were pregnancy rate (positive pregnancy test), clinical pregnancy rate (CPR) (ultrasound confirmation of a gestational sac with a yolk sac around 5-6 weeks), live birth rate, and miscarriage rate.

Results: Sperm morphology is a significant predictor of pregnancy rate (P = <.001), CPR (P =.011), and live birth rate (P = .026) following IUI. In each of these outcome measures, patients with 1% normal forms had the lowest percentage of success, and patients with 4% or greater normal forms had the most success. Relative outcome percentages, however, were similar in each group. Live birth rates in the 1%, 2%, 3%, and ≥4% group were 12.3%, 13.1%, 12.7%, and 13.9%, respectively. Sperm morphology is not a significant predictor of miscarriage rate per clinical pregnancy post-IUI (P = .054).

Conclusion: Sperm morphology was a statistically significant predictor of pregnancy, clinical pregnancy, and live birth but not miscarriage rate after an IUI cycle. Higher morphology percentages were associated with increasingly favorable outcomes. However, the small observed differences did not demonstrate clinical significance.