OBJECTIVETo investigate the values of the sperm deformity index (SDI), acrosome abnormity rate (AAR), and DNA fragmentation index (DFI) of optimized sperm in the prediction of fertilization failure (fertilization rate < 25%) in conventional in vitro fertilization (IVF).

METHODSWe selected 695 cycles of conventional IVF for pure oviductal infertility in this study, including 603 cycles of normal fertilization and 92 cycles of fertilization failure. On the day of oocyte retrieval, we examined sperm morphology, acrosome morphology, and DNA fragmentation using the Diff-Quik, PSA-FITC and SCD methods. We established the joint predictor (JP) by logistic equation and analyzed the values of different parameters in predicting fertilization failure with the receiver operating characteristic (ROC) curve.

RESULTSThe fertilization rate was negatively correlated with SDI (r = - 0.07; P = 0.03), AAR (r = -0.49; P < 0.01), and DFI (r = -0. 21; P < 0.01). The SDI, AAR, and DFI in the normal fertilization group were 1.24 ± 0.20, (7.75 ± 2.28)%, and (7.87 ± 3.15)%, and those in the fertilization failure group were 1.42 ± 0.15, (12.02 ± 3.06)%, and (13.32 ± 4.13)%, respectively, all with statistically significant differences between the two groups (P < 0.05). SDI, AAR, and DFI were all risk factors of fertilization failure ( OR = 2.68, 14.11, and 3.85; P = 0.01, < 0.01, and < 0.01). The areas under the ROC curves for SDI, AAR, DFI, and JP were 0.651 ± 0.033, 0.895 ± 0.019, 0.789 ± 0.022, and 0.915 ± 0.017, respectively. According to the Youden index, the optimal cut-off values of SDI, AAR, and DFI obtained for the prediction of fertilization failure were approximately 1.45, 10%, and 12%.

CONCLUSIONThe SDI, AAR and DFI of optimized sperm are closely associated with the fertilization rate, and all have the value for predicting fertilization failure in IVF. The AAR is more valuable than the other single predictors, but JP is more effective than the AAR.