Oocytes have repair ability for paternally derived DNA damage which depends on oocyte quality. Prolonged post ovum pick-up (OPU) incubation may lead to oocyte aging, which is linked to changes in oocyte ultrastructure and function. In order to study whether the effect of sperm DNA fragmentation (SDF) on intracytoplasmic sperm injection (ICSI) outcomes influenced by ICSI timing, we conducted this retrospective study included 1,331 ICSI cycles from March 2016 to December 2022. Outcomes were compared between two groups (an SDF level < 30% group and an SDF level ≥ 30% group) at different tertiles, which were based on OPU-ICSI time. There were no significant between-group differences in the overall laboratory and clinical outcomes (all p > 0.05). However, the clinical pregnancy rates (CPRs) (28.6% vs. 40.9%, p = 0.017) and live birth rates (LBRs) (21.4% vs. 33.4%, p = 0.014) were significantly lower in the SDF level ≥ 30% group than in the SDF level < 30% group in tertile 3. After adjusting for confounders, these differences remained significant, as shown by odds ratios (ORs) (95% confidence intervals (CIs)) of 0.425 (0.244, 0.742) for CPR and 0.485 (0.272, 0.865) for LBR. Significant between-tertile differences in outcomes were only found in the SDF level ≥ 30% group. In conclusion, ICSI timing affects the influence of SDF on the probability of live birth in women undergoing ICSI treatment. Therefore, in patients with high SDF levels, the optimal timing of ICSI should be determined.
Keywords: ICSI; ICSI timing; Live birth; Oocyte ageing; Sperm DNA fragmentation.
© 2025. The Author(s), under exclusive licence to Society for Reproductive Investigation.