Does last week's alcohol intake affect semen quality or reproductive hormones? A cross-sectional study among healthy young Danish men

The association between last 5days of alcohol intake, semen quality and reproductive hormones was estimated in this cross-sectional study among 347 men. Conventional semen characteristics, DNA fragmentation index and reproductive hormones (testosterone, estradiol, sex hormone-binding globulin (SHBG), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and inhibin B) were determined. There was a tendency towards lower semen characteristics at higher intake of alcohol past 5days, albeit with no statistically significant dose–response association. The ratio between free estradiol and free testosterone was higher at higher alcohol intake during the 5days preceding semen sampling. In conclusion, alcohol intake was associated with impairment of most semen characteristics but without a coherent dose–response pattern. The study indicates an association between recent alcohol intake and a hormonal shift towards higher estradiol/testosterone ratio. The hormonal changes observed may over time, lead to adverse effects on semen quality, but longitudinal studies are needed to study this.