An improved experimental model for understanding the impact of sperm DNA fragmentation on human pregnancy following ICSI.

Using donor oocytes of proven fertility, the effect of sperm DNA fragmentation (SDF) and motility on reproductive success was examined in 70 couples undergoing ICSI. Both SDF and sperm motility were assessed at the time of sperm injection and using the same sperm sample that was processed for ICSI. While there was no difference in the fertilization rate, cleavage rate, embryo quality, or sperm motility between pregnant and nonpregnant couples, the SDF of nonpregnant couples (SDF = 23.9%) was higher than that of pregnant couples (SDF = 17.0%; U Mann-Whitney 347; P = .002). Using a combination of the sensitivity and specificity measures from the production of ROC (receiver-operating characteristic) curves and the Youden index, we determined a threshold SDF value for our data set of 17% for predicting pregnancy (77.8% sensitivity and 71.1% specificity). Our results suggest that proven donor oocytes in combination with SDF assessment at the time of sperm injection represent a useful experimental model for reducing the confounding influences of sperm DNA repair by the oocyte and iatrogenic sperm damage.