Cytochemical evaluation of sperm chromatin and DNA integrity in couples with unexplained recurrent spontaneous abortions

Summary The aim of this study was to examine the possible relationship between sperm DNA integrity and chromatin packaging evaluated by cytochemical assays, traditional sperm parameters and recurrent spontaneous abortion (RSA) of unknown origin. In this cohort study, 40 couples with a history of RSA and 40 couples with proven fertility were considered as case and control groups respectively. The semen samples of all husbands were analysed for sperm parameters and also sperm chromatin and DNA integrity assessed using cytochemical tests including aniline blue (AB), chromomycin A3 (CMA3), toluidine blue (TB), acridine orange (AOT) and nuclear chromatin stability assay. Among different sperm parameters, only slow motility was significantly different between the two groups. In sperm chromatin evaluations, there were significant differences between the two groups in all of the tests. In addition, the majority of semen samples in RSA patients exhibited upper percentages of abnormal spermatozoa than the cut‐off values regarding different cytochemical assays. Our study showed that in the cases of RSA, slow motility had a significant reduction in comparison with controls and also spermatozoa of men from RSA group had less chromatin condensation and poorer DNA integrity than spermatozoa that obtained from fertile men with no history of RSA.