“The influence of marijuana use on human fertility has not been well studied. We evaluated the association between female and male use of marijuana and fecundability in Pregnancy Study Online, a prospective cohort of North American couples.
Men (14.2%) were more likely than women (11.6%) to be marijuana users. FRs for female marijuana use <1 and ≥1 time/week relative to non-use were 0.99 (95% CI 0.85 to 1.16) and 0.98 (95% CI 0.80 to 1.20), respectively. FRs for male marijuana use <1 and ≥1 time/week relative to non-use were 0.87 (95% CI 0.66 to 1.15) and 1.24 (95% CI 0.90 to 1.70), respectively. Associations for frequent marijuana use (≥1 time/week) were attenuated among non-smoking men (FR=1.21, 95% CI 0.84 to 1.74), but stronger among men reporting intercourse ≥4 times/week (FR=1.35, 95% CI 0.72 to 2.53).
In this preconception cohort study, there was little overall association between female or male marijuana use and fecundability.”