Marijuana smoking men are more fertile

Smoking marijuana increases fertility in men?

Physicians have now found that smoking cannabis can be associated with improved fertility in men. This effect also seems to persist if those affected have stopped consuming for a long time.

Scientists at the internationally acclaimed Harvard University found in their current research that smoking of cannabis appears to be associated with improved fertility in men. The researchers published the results of their study in the English language journal "Human Reproduction".

What have the findings found with testosterone to do?

The physicians examined for their study the sperm count of more than 600 men who have visited a fertility clinic. The experts actually expected that cannabis would affect sperm count and fertility. Instead, the participants who admitted they had ever taken the drug had higher sperm counts than non-users. This finding does not necessarily mean that cannabis smoking increases paternity chances, researchers say. However, the scientists point out that the association may not have a cause-and-effect relationship, but rather reflect the influence of the male hormone testosterone on both sperm count and risk behavior, such as smoking cannabis.

Further research is needed

These unexpected findings underscore how little is known about the consequences of marijuana's reproductive effects and, indeed, about the health effects of marijuana in general, study author Dr. Jorge Chavarro from the Harvard TH Chan School of Public Health in Boston in a press release. The results should, however, be interpreted with caution. They underline the need to further investigate the health effects of marijuana use.

Samples from 662 subjects were examined

For their new study, physicians examined a total of 1,143 semen samples from 662 men between the year 2000 and 2017. On average, the subjects were 36 years old, mostly white and had a college degree. All men lived in partnership and sought the help of a fertility clinic to improve conception or fertility. Participants were asked to fill in various questionnaires asking about their history of cannabis use, say the researchers.

Over half of the subjects had already smoked cannabis once

More than half (55 percent) of the men claimed to have smoked cannabis at some point in their lives. Forty-four percent of respondents said they had used cannabis in the past, eleven percent were current consumers. Analysis of the semen samples revealed that men who smoked marijuana had average sperm concentrations of 62.7 million sperm per milliliter (million / ml). If the subjects had never smoked cannabis before, the average concentration was only 45.4 million / mL, the authors of the study explain. Only five percent of cannabis users had levels below 15 million sperm per milliliter, the level that the WHO considers normal. If men had never smoked cannabis, low levels here were twelve percent. In addition, increased cannabis use was associated with increased levels of the male hormone testosterone in smokers of cannabis.

Possible explanations for the detected connection?

It is possible that a low exposure to cannabis promotes sperm production in some ways, the experts speculate. It is well known that the endocannabinoid chemical messenger system in the cannabis-targeted brain plays a role in regulating fertility, adds the physicians. An equally plausible interpretation is that the findings may reflect the fact that men with elevated testosterone levels are more risk-averse, which could include the use of marijuana, study author says. Feiby Nassan. (As)