Objective: To determine the effect of extremely low sperm morphology on pregnancy rates following intrauterine insemination (IUI) where all other semen parameters were normal.
Materials and methods: Retrospective review of all IUI cycles over a two-year period on infertile women age ≤ 35 where all parameters, but morphology had to be normal. The data were evaluated according to seven levels of percentage of normal morphology (NM): 0, 1, 2, 3, 4, 5, and ≥ 6%.
Results: The percent live delivery was 9.5, 16.7, 8.8, 16.1, 11.4, 12.3, and 10.9%.
Conclusions: Morphology of 0% or 1% did not seem to impair pregnancy rates following IUI. More studies are needed but should include determining the confounding effect of the type of morphologic abnormality.