Teenage girls who smoke marijuana may be permanently damaging their fertility, researchers warn.
A study led by the University of California, Irvine (UCI) found that adolescent female mice exposed to tetrahydrocannabinol (THC), the drug’s psychoactive chemical, had 50 percent less healthy ovarian follicles than the control group as adults. .
Researchers believe that the body’s endocannabinoid system, which is stimulated when marijuana is used, damages the follicles or causes them to activate too quickly, depleting them.
Now that marijuana use is common among teens across the United States, researchers fear that many young women may unknowingly hurt their chances of having a child in the future.
While the latest study was conducted in mice, separate research has shown that pregnant women who use cannabis are at increased risk of birth defects, miscarriages, and stillbirths.
Teens who smoke marijuana may be permanently damaging their fertility, researchers warn (file image)

The researchers found that mice that were regularly exposed to THC for two weeks had 50% fewer ovaries, including the primordial ovaries that represent the number of eggs a female will have for the rest of her life.

Marijuana is legal for recreational use in 21 US states and Washington DC (orange). It is available for medicinal use in 17 states (green)
“Given that more and more adolescents and young adults are using cannabis, especially with easier access to the substance, the findings of this study are especially important,” said Dr. Ulrike Luderer, the study’s lead author and a professor of environmental health at the ICU.
“It is imperative to disseminate widely the consequences of early cannabis exposure on reproductive health in later life.”
An estimated 3.3 million American teens between the ages of 12 and 17 use cannabis, experts warn.
The use of THC, the chemical within the drug that gives someone the ‘high’, has been legalized recreationally in 21 US states and the District of Columbia.
Nearly all of these states made the switch in the time since the covid pandemic, seeing increased tax revenue from marijuana sales as an opportunity to fill state coffers.
While already widely used as a street drug, its widespread legalization has skyrocketed marijuana use among America’s youth.
A study published late last year by the Oregon Health & Science University found that cannabis use among American adolescents increased 245 percent between 2000 and 2020.
There isn’t much research on the potential harms of the widespread adoption of cannabis.
However, early signs point to many negative long-term effects from the use of the drug, including heart problems, cognitive problems and lower IQ.
In November, researchers found that marijuana use increased a person’s risk of developing atrial fibrillation, a deadly heart condition, by more than 30 percent.
Now, the UCI study finds that young women in particular may put themselves at risk when using the drug.
The researchers, who published their findings in the Toxicological Sciences magazinehe injected mice that were around 30 days old with THC daily for two weeks.
These mice would be considered adolescents, as the species reaches adulthood at around three months of age.
When the mice reached 70 days of age, the researchers checked how many primordial follicle ovaries they had.
These are ovaries in the early stages. They will eventually develop into eggs that a woman will ovulate.
Like mice, human women are born with the ovaries they have had throughout their lives. A lower ovarian count significantly reduces your chances of getting pregnant in the future.
They found that mice that had been exposed to THC had half the ovaries of other mice of the same age.
This was the case at all stages of ovarian development, meaning that mice exposed to the drug were generally less fertile than their peers.
“Our findings provide unexpected new insights into the long-term impact of THC on reproductive function and aging,” said study co-author Dr. Daniele Piomelli and professor of anatomy and neurobiology at UCI.
“Our hope is that our findings will motivate adolescent girls to make better and more informed decisions about whether or not to ingest cannabis products.”
This is not the first study to link THC use to worse fertility.
A 2018 study found that men who smoked cannabis had lower sperm counts than their peers.