Frequent ejaculation. a pilot study of changes in sperm DNA damage and semen parameters using daily ejaculation

Abstract

To assess the effect of frequent ejaculation on sperm DNA damage and on semen parameters. Prospective study. 42 men with a raised SCSA level >15% were enrolled in the pilot study from a cohort of 138 couples investigated for either recurrent miscarriage of repeated IVF failure. Initial SCSA levels and semen parameters were assessed on all men after 3 days abstinence (D−3). <15% SCSA was considered normal, 15–27% low abnormal SCSA and >27% as high abnormal. Previous SCSA studies suggested a robustness of SCSA results on repeat testing and thus only one initial SCSA >15% triggered entry to the study. Once entered into the pilot trial treatment involved single daily ejaculation for 7 days and a repeat measurement of SCSA and semen parameters on the seventh day only (D + 7). Time between initial (D−3) sample and (D + 7) samples varied from 1–3 months and no other treatment options were offered or lifestyle changes requested. The mean SCSA level was 30.8% (range 15%–98%) measured after 3 days of abstinence (D−3). After 7 days (D + 7) ejaculation the mean was 20.0% (P<0.005). A decrease in SCSA was seen in 37 of the 42 men. (mean reduction 12.8%; P<0.005). An increase was seen in 5 of the 42 men with a mean of 10%. Semen analysis results showed the following. WHO strict criteria 1999. Count: Mean (D−3) 201.76 Million. Mean (D + 7) 67.6 Million. Motility: Mean Progressive mot (D−3) 42.8%. Mean (D + 7) 44.9% Morphology: Normal forms Mean (D−3) 3.16%. Mean (D + 7) 3.52% Previous studies have shown that increasing periods of abstinence is associated with increased sperm DNA damage. Presumably by increased exposure of the spermatozoa to secondary damage by reactive oxygen species (ROS). The results of this pilot study are consistent with the converse: that increasing the frequency of ejaculates could reduce the DNA damage presumably by reducing transit time through the epididymis and reducing exposure to ROS. Semen parameters showed a reduction in total count but no change in either motility or morphology after daily ejaculation for 7 days, providing a conspicuous contrast to the changes in SCSA. Further studies are required to confirm this pilot studies results.