Predictive value of sperm chromatin condensation (aniline blue staining) in the assessment of male fertility.
A case control study was carried out to determine the value of sperm chromatin condensation in the assessment of male fertility. A total of 165 semen samples from 90 patients (cases) and 75 healthy donors (control) were examined for chromatin condensation (aniline blue staining), as well as conventional sperm parameters, notably sperm morphology, sperm count, and progressive motility. Whereas only 55 +/- 12.0% of the samples from the infertile patients were unstained by aniline blue (chromatin condensed), 78 +/- 19.0% of the samples in the control group did not take up the stain (chromatin condensed). A significant difference (p < .001) was observed between the two groups. Similarly, the difference between the mean percentage of morphologically normal spermatozoa for the infertile patients (12.1 +/- 1.2%) and the control (23.9 +/- 1.9%) was very significant (p < .001). In addition, only 50 out of the 90 patients (55.5%) had a normal sperm count, whereas all the 75 (100%) were normal in the control group. By comparing between the two groups a significant difference (p < .001) was also observed. Furthermore, a significant difference (p < .001) was also found between the cases and the control with regard to the percentage of spermatozoa illustrating linear progressive motility (40 +/- 9.7% vs. 70 +/- 12.3%). However, no correlation was found between sperm chromatin condensation and morphology, count, and motility. This study suggests that chromatin condensation constitutes a valuable parameter in the assessment of male fertility, completely independent of conventional sperm parameters. Consequently, the inclusion of chromatin condensation to routine laboratory investigations of semen prior to assisted reproduction is strongly recommended.