Semen quality and alcohol intake: a systematic review and meta-analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of cross-sectional observational studies.
PubMed 28029592 · doi:10.1016/j.rbmo.2016.09.012
What was done
MEDLINE and Embase were searched for English-language, full-length observational articles evaluating the association between alcohol consumption and sperm parameters (volume, concentration, motility, morphology) reported as means or medians. Fifteen cross-sectional studies encompassing 16,395 men were included in the meta-analysis.
What was found
Alcohol intake was associated with reduced semen volume and normal morphology. No or low alcohol consumption was associated with higher semen volume compared to higher consumption (pooled estimate: 0.25 ml, 95% CI 0.07 to 0.42) and higher normal morphology (pooled estimate: 1.87%, 95% CI 0.86 to 2.88%). Differences were more marked when comparing daily consumers with occasional consumers than when comparing never drinkers with occasional drinkers. Results for sperm concentration or motility were not reported in the abstract.
Why it matters
This review suggests that moderate or occasional alcohol intake does not adversely affect semen parameters, whereas daily consumption is linked to minor reductions in volume and morphology.
Limits
All included studies were cross-sectional, precluding causal conclusions. The abstract does not provide data on sperm motility, concentration, or actual reproductive outcomes (such as fertility or pregnancy rates), nor does it report adjustment for potential confounding lifestyle factors like smoking.
Cited by
- supports Heavy alcohol consumption of 25 to 40 or more drinks per week drastically reduces sperm count and normal sperm morphology.