As for caffeine’s effect on the time needed to conceive a child, studies generally found no effect of moderate consumption. Men drinking fewer than three caffeine beverages per day shouldn’t be concerned that their caffeine habit will interfere with getting a partner pregnant.

The reviewers did return one disconcerting finding. A number of studies found that daily caffeine intake is associated with increased sperm DNA damage in the form of double-strand DNA breaks and aneuploidy, the presence of an abnormal number of chromosomes. Conceivably, such damage could lead to difficulty conceiving or a higher rate of genetic aberrations in children. This potential link is tenuous, however, and requires further study.