In a recent study published in the journal called Human Reproduction, researchers at Harvard University tested the sperm of 600 men at fertility clinics and evaluated their drug consumption habits, if any. 55% reported that they smoked cannabis at some point earlier. 11% said they used it at present. About 1,143 health surveys and semen samples at the Massachusetts General Hospital Fertility Centre were examined. Here is what the reports revealed, according to a U.K. news portal, The Independent, U.K.:
Half the men admitted to using cannabis in the past or present.
Only 5% of the cannabis user were found to have clinically low sperm counts compared to the 11% of those who never tried it.
Higher testosterone levels were reported in the cannabis user participants. (Higher testosterone has a key role in producing sperms.)
The reports are quite a contrast to previous ones that linked heavy cannabis use to lowered testosterone levels and lowered sperm production and quality. So the question arises: does smoking cannabis really lead to higher sperm count in men?
In an interview with Time magazine, the author of the journal explained that the spike in sperm count could be due to the effect of cannabis on the body’s endocannabinoid system which sends chemical messages in the brain, regulating fertility. However, he also mentioned that measuring past habits and the current sperm count do little to reveal the exact sperm count measurements prior to smoking the drug, hence does not prove whether it actually has any effect.
Dr. Jorge Chavarro and Dr. Feiby Nassan, authors of the study, explained it in a different way: "An equally plausible interpretation is that our findings could reflect the fact that men with higher testosterone levels are more likely to engage in risk-seeking behaviours, including smoking marijuana.”
Other findings on similar effects of cannabis use in men have been more sceptic. Before you reach out for your bongs, hear this:
Professor Sheena Lewis, from Queen's University Belfast has another explains, “Their sperm quality plummeted,” as the sperm became less mobile and less able to penetrate the wall of the egg. “Worst of all, sperm counts dropped and the nurse cells - also known as sertoli - that help to make sperm disappeared irreversibly.”
Fertility expert and professor of andrology at the University of Sheffield, Allan Pacey, said strict drug laws in many countries make it hard for high-quality trials to be completed, and so the evidence base remains inconclusive. In that light, it’s hard for researchers to come to a firm conclusions. “In my opinion, this (cannabis) should be avoided at all costs in any couples trying to start a family," he reportedly said.