Abstract
Semen analysis results from over 750 fathers in the USA demonstrated marked differences in the quality of semen from men at different locations and of different ethnic groups. Another paper failed to demonstrate any effects of moderate alcohol consumption during the week before provision of an ejaculate on semen quality and few on serum hormones, of over 8300 men in Europe and the USA. While these observations are interesting, the reasons for regional and ethnic differences in semen quality of fathers are unclear. Although, there was no attempt to confirm the participant-provided level of alcohol consumption, an increase in serum testosterone in the men at the higher end of alcohol intake is compatible with an alcohol effect on liver metabolism, although whether alcohol intake was the cause of higher testosterone, or men with higher androgen levels consume more alcohol, is not known.