Sperm DNA fragmentation index affect pregnancy outcomes and offspring safety in assisted reproductive technology

The role of sperm DNA fragmentation index (DFI) in investigating fertility, embryonic development, and pregnancy is of academic interest. However, there is ongoing controversy regarding the impact of DFI on pregnancy outcomes and the safety of offspring in the context of Assisted Reproductive Technology (ART). In this study, we conducted an analysis of clinical data obtained from 6330 patients who underwent in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) at the reproductive medical center of The First People's Hospital of Shangqiu and The Affiliated Hospital of Zhengzhou University. The patients was stratified into two distinct groups: IVF group and ICSI group, Within each group, patients were further classified into three subgroups. IVF: group A (< 15%) included 3123 patients, group B (15-30%) included 561 patients, and group C (≥ 30%) included 46 patients. ICSI: group A (< 15%) included 1967 patients, group B (15-30%) included 462 patients, and group C (≥ 30%) included 171 patients. Data were collected and subjected to statistical analysis. There were no significant differences in the basic characteristics among the three groups, and the sperm DFI did not significantly affect the fertilization rates, pregnancy rates, stillbirth rates and the number of birth defects. However, the incidences of miscarriage rates in IVF/ICSI groups with DFI > 30% and DFI 15-30% were significantly higher than those in IVF/ICSI groups with DFI < 15%, and the miscarriage rates in ICSI group with DFI > 30% were significantly higher than DFI 15-30% group, the smooth fitting curve shows that there is a positive correlation between miscarriage rates and sperm DFI (OR 1.095; 95% CI 1.068-1.123; P < 0.001). The birth weight of infants in the IVF/ICSI groups with DFI > 30% and DFI 15-30% exhibited a statistically significant decrease compared to those in the IVF/ICSI groups with DFI < 15%. Furthermore, the birth weight of infants in the ICSI group with DFI > 30% was lower than that of the DFI 15-30% group. The smooth fitting curve analysis demonstrates a negative association between birth weight and sperm DFI (OR 0.913; 95% CI 0.890-0.937; P < 0.001). Sperm DFI has an impact on both miscarriage rates and birth weight in assisted reproductive technology. The smooth fitting curve analysis reveals a positive correlation between miscarriage rates and DFI, while a negative correlation is observed between birth weight and DFI.