Marijuana Cuts Male Fertility By Mutilating Sperm
Potheads may be disfiguring their sperms. New research reveals that young me who smoke marijuana may be decreasing their fertility by inadvertently affecting the size and shape of their sperm
Scientists from the University of Sheffield and Manchester also found that men produced worse sperm in the summer months. However, sperm shape and size was better in men who abstained from sexual activity for more than six days.
Surprisingly, other smoking cigarettes and drinking alcohol appeared to have little effect on sperm morphology.
The latest study involved d 2,249 men from 14 fertility clinics around the UK. Participants were asked to fill out questionnaires about their medical history and lifestyle. However, information on sperm morphology was only available for 1,970 men.
In the study, researcher compared the 318 men who produced sperm of which less than 4 percent was the correct size and shape to a control group of 1,652 "normal" men who produced normal sperm morphology above 4 percent.
The findings revealed that men who ejaculated less than 4 percent of normal sperm were nearly twice was likely to have given a sample during the summer months, or to have used marijuana in the three months before providing the sample.
"Our knowledge of factors that influence sperm size and shape is very limited, yet faced with a diagnosis of poor sperm morphology, many men are concerned to try and identify any factors in their lifestyle that could be causing this. It is therefore reassuring to find that there are very few identifiable risks, although our data suggests that cannabis users might be advised to stop using the drug if they are planning to try and start a family," lead author Dr Allan Pacey, Senior Lecturer in Andrology at the University of Sheffield, said in a news release.
"This research builds on our study of two years ago3 which looked at the risk factors associated with the number of swimming sperm (motile concentration) in men's ejaculates," Dr. Andrew Povey, from the University of Manchester's Institute of Population Health, said in a statement.
"This previous study also found that there were relatively few risk factors that men could change in order to improve their fertility. We therefore have to conclude again that there is little evidence that delaying fertility treatment to make adjustments to a man's lifestyle will improve their chances of a conception," Povey added.
"In addition to cannabis exposure shown in this paper, we also know that men exposed to paint strippers and lead are also at risk of having sperm with poor morphology," noted Professor Nicola Cherry, originally from the University of Manchester but now at the University of Alberta.
The findings were published in the Journal of Occupational and Environmental Medicine.