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Temporal shifts in semen parameters across a major COVID-19 outbreak wave: a retrospective cohort study using
Hai Wang1, Xianjue Zheng1, Haojie Pan1
1Center for Reproductive Medicine, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, Wenzhou, China.
Objective:
To investigate the temporal variations in male semen quality parameters before, during, and after a major regional COVID-19 outbreak wave.
Methods:
This retrospective cohort study analyzed initial semen samples collected at our hospital between June 1, 2022, and June 30, 2023. Based on regional epidemiological data corresponding to a major outbreak, participants were stratified into three groups by sample collection date: a pre-outbreak group (Group A, September 1, 2022-December 31, 2022, n = 330), a peak-outbreak group (Group B, January 1, 2023-March 31, 2023, n = 413), and a post-outbreak group (Group C, April 1, 2023-June 30, 2023, n = 480). Conventional semen parameters, sperm acrosin activity, and sperm DNA fragmentation index (DFI) were compared.
Results:
The peak-outbreak group (Group B) showed significantly lower sperm concentration compared to both the pre-outbreak group (49.1 vs. 59.6 × 106/ml, P = 0.009) and the post-outbreak group (49.1 vs. 62.6 × 106/ml, P < 0.001). Similarly, progressive motility was significantly lower in the peak-outbreak group (37.7%) compared to the pre-outbreak (45.1%, P < 0.001) and post-outbreak groups (43.4%, P < 0.001). No significant differences were found in these parameters between the pre-outbreak and post-outbreak groups (P > 0.05). Sperm acrosin activity and DFI remained stable across all three groups (P > 0.05).
Conclusion:
Semen concentration and motility were significantly lower in samples collected during the peak of a major COVID-19 outbreak wave, with parameters returning to pre-outbreak levels in the subsequent 3-month period. Key sperm functional biomarkers, including acrosin activity and DNA integrity, appeared resilient throughout these distinct epidemiological phases.
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