Effect of sperm chromatin condensation on the outcome of intrauterine insemination in patients with male factor infertility.

OBJECTIVE: To study the effect of sperm nuclear chromatin condensation on pregnancy rates and rates of abortion in infertile couples with male factor infertility undergoing intrauterine insemination. STUDY DESIGN: A total of 195 infertile couples with male factor infertility undergoing intrauterine insemination (IUI) were included in this prospective study. They were divided into two groups according to sperm chromatin staining by aniline blue stain. The first group included 109 patients having a positive aniline blue staining in < 30% of sperm. The second group included 86 infertile couples in whom > or = 30% spermatozoa were positively stained. All cases were assessed clinically and underwent semen analysis and assessment of chromatin condensation by aniline blue staining. IUI with the partner's sperm was done after semen processing and induction of ovulation; pregnancy rate and rate of abortion were recorded. RESULTS: The pregnancy rate in the first group was 21.6% (24/111), and abortions occurred in 29.2% (6/24). In the second group the pregnancy rate was 18.6% (16/84) and abortions occurred in 56.3% (9/16). There was no statistically significant difference in pregnancy rate between the two groups, while the rate of abortion increased with increased sperm chromatin decondensation. CONCLUSION: Our study concluded that sperm chromatin condensation has no effect on the pregnancy rate, but it has a profound effect on fertilization failure after IUI, therefore assessment of sperm chromatin condensation may be useful as a predictive test for successful pregnancy after intrauterine insemination.