Usefulness of sperm penetration assay in fertility predictions
The competence of the sperm penetration assay (SPA) to predict male fertility, as determined by normal sperm morphology and the fertilizing potential, as shown by human in vitro fertilization (IVF), was investigated. A significant correlation was obtained between normal sperm morphology and the SPA (Φ = 0.623). A weaker correlation was however obtained with human IVF (Φ = 0.397). Notwithstanding this weak association, a positive SPA (> 10%) was highly predictive (95%) of human IVF success. In contrast, a negative SPA (≤ 10%) was associated with a high rate of false-negative (65%). The SPA does however warn that a male factor may be present, as the mean fertilation rate of this group of patients was markedly reduced. The preincubation period for the spermatozoa did not play a major role in the predictive ability of a SPA outcome.