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. After analyzing the ejaculate of more than 600 men, researchers from the Harvard T.H. Chan School of Public Health found that men who reported using cannabis had higher sperm counts than men who reported never using cannabis. That's not what we, or the researchers, expected to hear.
For the study, published in the scientific journal Human Reproduction, researchers went straight to the source—a fertility clinic in Massachusetts—to examine the connection between sperm count and cannabis, collecting 1,143 semen samples from 662 male patients. These men also filled out a questionnaire about their marijuana use, past and present, and half the men had blood samples taken to test for reproductive hormone levels. The researchers found that men who reported smoking marijuana had, on average, "significantly higher" sperm concentrations than men who did not smoke: 62.7 million sperm per milliliter of ejaculate in smokers versus 45.4 million sperm per milliliter of ejaculate in non-smokers.
