Researchers at Harvard University published an interesting discovery this week, after a controlled fertility study demonstrated a positive correlation between lifetime cannabis use and high sperm count in adult men.
According to Bloomberg, the new study, published in the journal Human Reproduction, examined 1,143 semen samples from 662 men who had visited the Massachusetts General Hospital fertility clinic from 2000 to 2017. As part of an extensive participant questionnaire, researchers asked the subjects whether or not they had smoked two or more marijuana joints in their life.
After counting up the swimmers in each sample and comparing it back to the person it came from, Harvard researchers found that participants who had checked the ‘yes’ box on the cannabis question tested at a mean concentration rate of 62.7 million sperm per milliliter of ejaculate, as opposed to the folks who had never tried marijuana, who tested at a mean concentration of 45.4 per milliliter.
For decades, researchers have worked under the assumption that cannabis may decrease men’s sperm count, often citing addiction studies published in the 1990s. But with the new study suggesting the exact opposite, the Harvard researchers are reconsidering the relationship between cannabis and fertility.
"These unexpected findings highlight how little we know about the reproductive health effects of marijuana, and in fact of the health effects of marijuana in general,” Dr. Jorge Chavarro, a lead researcher on the study, told Bloomberg.
Dr. Chavarro and his colleagues noted that low doses of cannabis could potentially help fertility, but made sure to avoid any strict causal assumptions about the correlation between sperm count and joint smoking. The scientists also suggested that the results could have been caused by a number of factors, including the possibility that men with higher testosterone levels (and thus higher sperm counts) may simply be more likely to engage in risky behavior like using cannabis.
"Our results need to be interpreted with caution and they highlight the need to further study the health effects of marijuana use," Dr. Chavarro stressed.
Whatever the cause, though, the new study suggests that it may be time to put a pin in the old way of thinking, and break out the bong before you get down to baby making.
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