Marijuana use could potentially lower a person’s sperm count, making it more difficult to have children
Cannabis can affect the body in a number of ways, including sperm concentration, a new study from Duke University found.
The small study, which looked at the sperm of 37 men who either used or did not use cannabis, concluded that use of the substance can significantly change a person’s sperm concentration. The study also looked at how cannabis use affected ejaculation, semen volume, semen pH, and motility, and found that the substance did not create a significant change in these categories.
“What we have found is that the effects of cannabis use on males and their reproductive health are not completely null, in that there’s something about cannabis use that affects the genetic profile in sperm,” Scott Kollins, a senior author of the study, said in a statement.
Sperm concentration affects a person’s ability to conceive, so a lower concentration could make it more difficult to have a child
Sperm concentration, along with other factors like sperm motility and testosterone levels, can affect a person’s ability to conceive a child, according to the Mayo Clinic. So the study’s findings suggest a person who uses cannabis may have more difficulty conceiving than someone who does not use cannabis.
This factor is important because if fewer sperm are present in a person’s semen, there is a decreased chance that a sperm will reach an egg and fertilize it. According to the Mayo Clinic, a low sperm count or concentration means a person has fewer than 15 million sperm per milliliter of semen. To determine a person’s sperm count, doctors must look at semen under a microscope on two separate occasions for accuracy purposes, the Mayo Clinic explained.
There’s a chance genetic sperm changes from cannabis use could be hereditary, but more research needs to be done
Since sperm concentration can greatly affect a person’s reproductive abilities, the study’s authors also looked at the potential for this trait to be passed from a cannabis user down to their offspring. Based on previous studies about cigarette smokers’ ability to pass on certain traits, they found that there is a chance cannabis users who have genetically-changed sperm might cause their children to also have genetically changed sperm.
Since the sample size of the study was relatively small, however, more research must be done to understand how cannabis affects a person’s sperm and how those genetic-level changes could be passed down to offspring.
A new study found that people who use marijuana might have lower than normal sperm concentrations, which could make it harder to conceive.
Marijuana Does Affect Men’s Sperm, And Here’s How
If you’ve been confused by the facts surrounding the impact smoking weed can have on a man’s sperm count, you’re not alone. Here’s what experts are saying.
Marijuana use in America is clearly booming—10 states have made its use legal, and 9 more states projected to make it legal in 2019.
And its estimated that 16.5% of adults in the U.S. use marijuana.
With its popularity gaining, research on marijuana’s health benefits and risks have become robust. And when it comes to fertility, it’s become a hotly debated (and studied) topic to learn about its impacts on sperm and sperm health. Is marijuana use good or bad for sperm?
First, you should understand how marijuana effects sperm.
“Tetrahydrocannabinol (THC), the active compound of marijuana, binds to receptors in many different glands and tissues that are involved in sperm production,” says Matthias Hofer, MD, urologist at Northwestern Memorial Hospital. “These receptors are found in the hypothalamus and pituitary gland, decreasing hormone production necessary for sperm production.”
When it comes to research, most studies have concluded that marijuana is not good for sperm.
“There are many lab studies showing negative effects of marijuana on sperm. There are surprisingly few human trials, but they all demonstrate that cannabis use reduces sperm concentration, sperm motility (ability to swim), or both,” says Doron Stember, MD, assistant professor of urology at the Icahn School at Mount Sinai.
Experimental laboratory studies showed that THC decreased the number of mobile sperm by up to 20%, and also inhibited the ability to fertilize an egg, adds Dr. Hofer. Men who used marijuana more than once a week had a nearly 30% decrease in sperm count compared to those men not using THC, and a 5% decrease compared to those with less frequent use.
Besides the impact on sperm count and mobility, it was also found to fundamentally change the sperm itself.
And a study published in the journal Epigenetics found that marijuana actually mutates DNA in sperm.
Plus, cannabis use has also been found to decrease men’s ability to orgasm.
If the evidence seems stacked against marijuana use, there have also been some studies that negate marijuana’s negative effects on fertility.
And a 2019 study published in the journal Human Reproduction found that men who reported using cannabis had “significantly higher” sperm counts than men who reported never using cannabis.
One study also showed that cannabis use was associated with—but did not necessarily cause—higher testosterone levels.
While this can complicate a finite answer, doctors do believe more research needs to be done.
“While the scientific evidence that THC negatively impacts fertility at many levels is abundant, it should be noted that some of these studies are limited by low patient numbers, and that a subset of studies found contradictory results,” says Dr. Hofer. “Clinical trials, the highest quality study type producing the most reliable results, have not yet been performed and would provide further clarification.”
But if you do smoke marijuana and have difficulty conceiving, it may not be the sole root cause of your infertility issues.
“Fertility can be affected by many factors and THC is just one of them,” says Dr. Hofer. “Although there is ample evidence that sperm count and quality is affected by THC, if considering fertility overall (lower sperm count may still be sufficient for conception) it appears that there is no difference in the probability of couples getting pregnant among those using marijuana compared to those that did not, according to a recent study.”
Another note: the method of marijuana consumption (i.e. smoking vs. edibles), is likely has the same impact on sperm.
“Resorption of THC occurs after inhalation and also after ingestion and the effect on sperm can be assumed to be similar,” says Dr. Hofer.
However, adds Dr. Stember, “No studies comparing the effects of smoking, vaping, or eating marijuana have been performed.”
So should men stop using marijuana if they’re trying to conceive with their partner?
While the research has gone both ways about marijuana’s impact on sperm, doctors do not recommend men using marijuana.
“Based on the current evidence, it may be advisable to stop THC intake when conception is planned, even if the sperm count would likely be sufficient in absence of other factors associated with decreased sperm count,” says Dr. Hofer.
And Dr. Stember agrees.
“Men who are worried about their fertility potential should stop or reduce their marijuana use. The impact of marijuana on sperm seems to be dose-dependent. The more marijuana used, the more likely a man is to have sperm problems,” says Dr. Stember.
If you've been confused by the facts surrounding the impact smoking weed can have on a man's sperm count, you're not alone. Here's what experts are saying.