A Washington State University study found that mice who were exposed to cannabis in “intense,” yet small amounts, had low sperm counts and slow sperm movement, not only in the mice who were directly exposed to cannabis vapor but also to the next generation of offspring.
The study is the first of its kind to use cannabis vapor, traditionally, studies using animals for the study of cannabis are injected with tetrahydrocannabinol (THC), the psychoactive component of cannabis.
Thirty male mice were used in the study with fifteen being exposed to an intense amount of cannabis vapor three times a day for ten days, this mimics the use of a frequent cannabis user.
An unofficial study done by wikileaf surveyed 131 daily smokers and found that the highest percentage of daily smokers, at 51.9 percent, said they smoked less than a gram of cannabis a day.
The Washington State University study used the cannabis exposed mice, who were compared by their sperm counts and the movement of their sperm, to fifteen unexposed mice and it was found that right after exposure to cannabis the movement of sperm in the exposed mice had slowed and a month later their sperm count was lower.
Several of the exposed mice were then bred with unexposed females and the offspring were found to have lower sperm counts and the sperm’s movement had slowed.
According to Kanako Hayashi, who is the co-author of the study and an associate professor in WSU’s School of Molecular Biosciences, evidence of DNA damage was found and sperm cells weren’t fully developed.
“We were not expecting that the sperm would be completely gone or that motility (movement) would be completely offset, but the reduction in sperm count and motility of the offspring, the sons, is probably a direct effect of the cannabis exposure to father,” said Kanako.
A third-generation was bred and there were no signs of low sperm count or low sperm mobility in grandsons of the exposed mice, which Hayashi and her team concluded that the cannabis exposure only affected the exposed offspring during the developmental stage.
According to the Mayo Clinic, Cannabis can stay in a daily user’s system anywhere from ten to fifteen days after their last use, so The Dallas Express asked Ms. Hayashi, If the first generation of mice who were exposed to cannabis vapor weren’t mated to unexposed females until after the cannabis was no longer detectable in the mice systems, would their sperm count get back to healthy levels and would there would be less of a chance that the second generation of male mice to have a low sperm count and low sperm motility?
“Although we don’t know the exact THC level when the male was bred with females, [for the study] it is not critical whether THC or other THC metabolites are detectable in the plasma or uterine, etc. It is important how much damage testis or sperm get during the exposure and it is still sustained.”
There have been claims that popular vitamins such as Ashwagandha or increasing antioxidant intake would help boost sperm count however Hayashi says she “wasn’t sure” if these supplements would reverse low sperm count or increase sperm mobility as they have yet to test supplements on mice.
The study is ongoing as there are plans to work with females who would be exposed to cannabis, in the same way, to determine any issues and if cannabis exposure to mice in-utero would create reproductive issues that could be passed down.
