“Men who had ever smoked marijuana had significantly higher sperm concentration than men who had never smoked marijuana after adjusting for potential confounders.
These findings are not consistent with a deleterious effect of marijuana on testicular function.”
“SMOKING MARIJUANA APPEARS TO UP MEN’S SPERM COUNT—TO THE SURPRISE OF SCIENTISTS” https://www.newsweek.com/smoking-marijuana-appears-men-sperm-count-surprise-scientists-1318138
“Cannabis Smoking Associated With Higher Sperm Count, Study Finds” https://www.bloomberg.com/news/articles/2019-02-06/cannabis-smoking-associated-with-higher-sperm-count-study-finds
“Smoking cannabis has unexpectedly been linked to greater fertility in men.” https://www.independent.ie/world-news/north-america/smoking-cannabis-can-make-men-more-fertile-say-scientists-37787137.html