Much research has linked cigarette smoking to both male and female infertility. But while the impact of nicotine on fertility has been researched for decades, you may be surprised to learn that marijuana, too, can impact male fertility — and its effect may be more severe than tobacco.
According to new research published in the American Urological Association’s Journal of Urology in April 2019, men who smoked marijuana had more sperm functional defects than those who smoked cigarettes. For the study, Brazilian researchers looked at data on 622 men between the ages of 18 and 59. The men were split into four groups: marijuana smokers, tobacco smokers, men with diagnosed infertility and a fertile control group.
Marijuana’s detrimental impact on sperm quality and testicular function is due to increased production of reactive oxygen species (ROS), which can damage cell structure and degrade the quality of semen. Semen ROS levels were 20 times higher in marijuana users than cigarette smokers, according to study author Jorge Hallak, MD, of the University of Sao Paulo, who spoke about the researchers’ conclusions at the American Urological Association annual meeting.
“Overall, the marijuana group had semen quality equivalent to the infertile group, with the exception of higher ROS and DNA damage than infertile men,” said Hallak in an American Urological Association press briefing, per MedPageToday. “DNA damage is higher in all groups [marijuana users, smokers and infertile men] as compared to controls, but higher levels were found in the marijuana group and infertile men.”
Key takeaway for all the fellas out there? To keep your swimmers healthy, you may want to lay off the weed.