Effects of alcohol use on sperm chromatin structure, a retrospective analysis.

Background: The evaluation of the infertile couple is often complex as multiple factors in both the male and female can contribute, including social history. Previous studies have displayed that male ethanol consumption can disturb sperm motility, nuclear maturity, and deoxyribonucleic acid (DNA) integrity. The main purpose of this study is to evaluate the effects of male alcohol use on sperm chromatin structure analysis (SCSA®). This study was a retrospective chart review of 209 couples that presented to a midsize infertility clinic in the Midwest and had a semen analysis and SCSA® performed. Data extracted from the electronic medical record included demographics, tobacco use, alcohol use, occupational exposures, semen analysis results, and SCSA® results (DNA Fragmentation index (DFI) and High DNA stainability (HDS)). Statistical analysis was performed on this data set to determine significance with a p-level of 0.05, with the primary input being level of alcohol use and primary outcome being the SCSA® parameters.

Results: Overall, 11% of the cohort had heavy alcohol use (> 10 drinks/week), 27% moderate (3-10/week), 34% rare (0.5- < 3/week), and 28% none. 36% of the cohort had HDS > 10% (a marker of immature sperm chromatin). Level of alcohol use was not significantly associated with HDS > 10% or DFI. Heavier alcohol use was significantly associated with lower sperm count (p = 0.042). Increasing age was significantly associated with increasing DNA Fragmentation Index (p = 0.006), increased sperm count (p = 0.002), and lower semen volume (p = 0.022). Exposure to heat at work was significantly associated with lower semen volume (p = 0.042). Tobacco use was associated with lower sperm motility (p < 0.0001) and lower sperm count (p = 0.002).

Conclusions: There was not a significant association between the level of alcohol use and the High DNA Stainability or DNA Fragmentation Index of sperm. Increasing age was associated with semen parameters as expected, heat exposure was associated with lower semen volume, and tobacco use was associated with lower sperm motility and density. Further studies could investigate alcohol use and reactive oxidative species in sperm.