To determine the effect of sperm morphology from the specific sample used for intrauterine insemination (IUI) on clinical pregnancy rates (CPR).
Prospective cohort study.
Academic fertility clinic.
Couples undergoing IUI July 2016–January 2017.
Morphology slides were prepared from the semen sample produced for IUI.
Main Outcome Measure(s)
CPR was measured by detection of cardiac activity. Multiple logistic regression modeling was performed to determine the association of sperm morphology with CPR, controlling for age, antimüllerian hormone level, and post-wash total motile sperm count.
Semen analyses, including Kruger strict criteria for morphology from the actual sample inseminated, were reviewed for 155 couples, comprising 234 total treatment cycles. The percent normal morphology significantly differed between the preliminary semen analysis and the IUI sample (−2.0% +3.7% (95% CI −2.55, −1.53). Of the total 234 treatment cycles, 8.6% resulted in clinical pregnancy. When categorized by strict morphology >4%, <4%, and <1%, the CPR was 6.6%, 9.8%, and 10.9%, respectively. In couples with otherwise normal semen parameters (isolated teratospermia), CPR by >4%, <4%, and <1% normal forms was 7.2%, 9.8%, and 11.1%, respectively. There was no significant association between the percent normal morphology and CPR in multivariate analysis.
This study evaluating the morphology of the actual inseminated sample did not find differences in CPR following IUI among couples with normal and abnormal sperm morphology, including severe teratospermia. Abnormal sperm morphology should not exclude couples from attempting IUI.