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Intracytoplasmic Sperm Injection (ICSI) Timing Affects the Influence of Sperm DNA Fragmentation on ICSI Outcomes
Gaofeng Yan1, Dan Tang2, Zhenfang Su1
1Reproductive Genetics Department, The first affiliated hospital of Kunming Medical University, Kunming, 650032, China.
Abstract:
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.
Insights
Intracytoplasmic sperm injection (ICSI) timing impacts live birth rates, especially for men with high sperm DNA fragmentation (SDF). Optimizing ICSI timing is crucial for improving outcomes in these patients.
Area of Science:
- Reproductive Medicine
- Embryology
- Infertility Treatment
Background:
- Oocyte DNA repair capacity varies with oocyte quality.
- Prolonged incubation post-ovum pick-up (OPU) can lead to oocyte aging, affecting ultrastructure and function.
- Sperm DNA fragmentation (SDF) can impact intracytoplasmic sperm injection (ICSI) outcomes.
Purpose of the Study:
- To investigate if ICSI timing influences the effect of SDF on ICSI outcomes.
- To compare ICSI results between different SDF levels based on OPU-ICSI time intervals.
Main Methods:
- Retrospective study of 1,331 ICSI cycles (March 2016 - December 2022).
- Patients categorized into SDF < 30% and SDF ≥ 30% groups.
- Outcomes analyzed across tertiles based on OPU-ICSI time.
Main Results:
- No significant differences in overall laboratory or clinical outcomes between SDF groups.
- In the longest OPU-ICSI interval (tertile 3), the SDF ≥ 30% group had significantly lower clinical pregnancy rates (CPRs) and live birth rates (LBRs).
- Adjusted analysis confirmed lower CPRs (OR 0.425) and LBRs (OR 0.485) for the high SDF group in tertile 3.
Conclusions:
- ICSI timing significantly affects the impact of SDF on live birth probability.
- For patients with high SDF levels, determining optimal ICSI timing is essential for successful treatment outcomes.
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