Men who have smoked marijuana may be more fertile than those who have never touched it, suggests a new study published in the journal Human Reproduction. While research about marijuana and fertility is limited, some past papers have suggested that it might harm semen quality. Cigarette smoking is also known to be a risk factor for both female and male infertility. Given those links, the authors of the new study expected to find that men who have smoked pot would have worse measures of fertility, says co-author Dr. Jorge Chavarro, an associate professor of nutrition and epidemiology at the Harvard T. Chan School of Public Health.
Is marijuana smoking associated with semen quality, sperm DNA integrity or serum concentrations of reproductive hormones among subfertile men? Men who had ever smoked marijuana had higher sperm concentration and count and lower serum FSH concentrations than men who had never smoked marijuana; no differences were observed between current and past marijuana smokers. Studies of marijuana abuse in humans and animal models of exposure to marijuana suggest that marijuana smoking adversely impacts spermatogenesis. Data is less clear for moderate consumption levels and multiple studies have found higher serum testosterone concentrations among marijuana consumers.
Nassan FL, et al. Human Reproduction. Men who had ever smoked marijuana had significantly higher sperm concentrations than men who did not, according to findings recently published in Human Reproduction. Chan School of Public Health, and colleagues. Another previous study concluded that men who smoked marijuana more than once a week had significantly lower sperm counts , but significantly higher serum testosterone concentrations, they added.
For ages, the conventional wisdom about marijuana and male reproductive health was that one did not benefit the other. Weed was kryptonite for healthy sperm; don't partake in one if you want the other. Scientific studies backed that up. But all it takes is one new study to blow up what we thought we knew, and that study was published this month.