Alcohol and male reproductive health: a cross-sectional study of 8344 healthy men from Europe and the USA.

Plain-language summary

This study asked whether alcohol relates to semen quality and reproductive hormones in healthy men. It pooled 8,344 men from Europe and the United States, 1,872 fertile men with pregnant partners from four European cities and four US states, and 6,472 young men of mostly unknown fertility from the general population in six European countries, all of whom reported a week of drinking and gave semen and blood samples. Moderate drinking, which was most of this group, did not show a consistent relationship with any semen measure. Total alcohol did track with total and free testosterone, rising as intake rose. It did not track with FSH (follicle-stimulating hormone, the pituitary signal that drives sperm production, where a high reading usually means the testicles are being pushed harder than they should need), with LH, or with inhibin B (a hormone made by the testicles that reflects how much sperm-producing tissue is working, where higher is better). This study shares four authors and part of its recruitment programme with another study in this library, on sleep and semen quality, so the two are not independent evidence.

Key findings

• No consistent association between moderate alcohol intake and semen quality.
• Higher alcohol intake was linked to higher total and free testosterone levels.
• No significant association between alcohol intake and other reproductive hormones like FSH, LH, or inhibin B.