Sperm Morphology Evaluated by Computer (IVOS) Cannot Predict the Fertilization Rate In Vitro after Intracytoplasmic Sperm Injection

Objective: To evaluate sperm morphology assessment using the IVOS (Hamilton-Thorne Research Version 3 Dimension Program, Beverly, MA) system in prediction of fertilization rate in vitro after intracytoplasmic sperm injection (ICSI). Design: A prospective clinical study. Setting: Diagnostic andrology laboratory and assisted conception service. Patient(s): Thirty-five patients from the ICSI program were evaluated. Semen samples were analyzed using a computerized system for conventional semen parameters, sperm movement characteristics, and sperm morphology. Only patients with three or more metaphase II (MII) oocytes available were studied. Intervention(s): None. Main Outcome Measure(s): Fertilization rates in vitro after ICSI were compared according to the sperm morphology obtained from the IVOS system. Result(s): Linear regression analysis of fertilization rates against the sperm parameters assessed by computer (IVOS), which included conventional semen parameters, sperm movement characteristics, percentage of normal sperm morphology, and percentage of each specific abnormal sperm morphology, did not reveal any significant correlations. The mean (±SEM) fertilization rates in the healthy prognosis group (normal sperm morphology ≥4%) and poor prognosis group (normal sperm morphology ≤4%) were 82.4 ± 4.0% and 75.0 ± 3.8%, respectively. There was no statistically significant difference in the mean fertilization rate between both groups. Moreover, no statistically significant difference was found in overall fertilization rates in vitro between the two prognosis categories (79.6% versus 78.0%). Conclusion(s): Sperm morphology obtained from the IVOS system is not related to the outcome of ICSI and cannot be used for prediction of fertilization rate in vitro after ICSI.