Association between sperm cell chromatin condensation, morphology based on strict criteria, and fertilization, cleavage and pregnancy rates in an IVF program.

In this study, a total of 95 ejaculates from infertile patients were investigated morphologically according to Kruger's strict criteria and 78 of the 95 ejaculates were stained for chromatin condensation with acidic aniline blue. Patients were divided into two groups based on the percentage of morphologically normal spermatozoa as follows: Men with normal sperm morphology < 14% (Group 1), and men with normal morphology > 14% (Group 2). The relationship between percentage of normal sperm morphology and fertilization, cleavage and pregnancy rate was analysed. The rates were 33.7%, 57.1% and 0.0% respectively, in the first group. The corresponding values for the second group were 76.1%, 68.2% and 32.1%. The fertilization and pregnancy rates correlate significantly with morphologically normal spermatozoa. In regard to the percentage of morphologically normal spermatozoa stained with aniline blue, patients were divided into two groups: patients with 0-20% stained spermatozoa (Group I) and those with > 20% (Group 2). Fertilization and pregnancy rates were higher in the first group than in the second group (79.9%, 52.8% vs. 58.8%, 29.5%). The results demonstrate that chromatin condensation visualized by aniline blue staining is a good predictor for IVF outcome and should be considered besides morphology by sperm assessment for patients undergoing IVF treatment.