Marijuana use reduces male fertility by depleting sperm before it reaches the egg, causing fertility issues and lowering pregnancy chances.
Yes, marijuana can affect fertility in both men and women.
Cannabis or marijuana is legal for medical or recreational use in all states except 11, and in 2021, at least 52.5 million Americans used it at least once, according to the Centers for Disease Control and Prevention.
However, since it remains illegal under federal law, it is difficult to study, and its long-term health effects are still not well understood, said Omer Raheem, a urologist at the Cleveland Clinic who practices in the U.S. and Abu Dhabi.
Studies suggest the following effects:
In men:
Decreased semen quality: Chronic marijuana use has been linked to a reduction in sperm count, motility, and normal morphology. The cannabinoids in marijuana can alter sperm physiology, depleting their energy and impairing their ability to fertilize the egg.
Hormonal changes: Marijuana can lower testosterone levels, which may lead to decreased libido and even erectile dysfunction.
Testicular function: Chronic marijuana use can negatively affect testicular function and even reduce testicular size.
Sperm DNA damage: Some studies suggest marijuana may alter sperm DNA quality.
Finally, animal research suggests that cannabis may affect the DNA inside sperm that contributes to the new embryo. A 2020 study on rats by Duke scientists found that paternal cannabis use impaired the offspring’s brain development.
In women:
Hormonal changes: Marijuana use can raise prolactin levels, a hormone typically produced during breastfeeding. This can disrupt the hypothalamic-pituitary axis, leading to anovulatory cycles (lack of ovulation), irregular menstrual cycles, or even amenorrhea (absence of menstruation).
Implantation issues: Some studies suggest marijuana may hinder embryo implantation in the uterus.
Higher miscarriage risk: Marijuana use has been linked to an increased risk of miscarriage.
Tubal problems: Marijuana could affect the motility of the fallopian tube fimbriae, which are important for transporting the egg and fertilized embryo to the uterus, potentially increasing the risk of ectopic pregnancy.
Oocyte and embryo quality: In assisted reproduction cycles, marijuana use has been associated with poorer egg and embryo quality, reducing pregnancy chances.
How to mitigate the risk
Of course, cannabis can also affect male sexual health in ways unrelated to sperm.
“Chronic use at high doses can contribute to erectile dysfunction, delayed ejaculation, and long-term decreased sexual desire,” said Ryan S. Sultan, a clinical psychiatrist at Columbia. He warned that even smoking just once a week could trigger some of these effects.
Men should stop using cannabis for at least three months before trying to conceive, said Ryan Vandrey, who researches cannabis use at Johns Hopkins University.
However, “there are many men of reproductive age who use a lot, a lot of cannabis and are having children,” he added. “So it’s not that you can’t have a child if you use a lot of cannabis daily.”
Sultan recommended switching to edibles or vaping products. But while these other methods of cannabis consumption may have fewer harmful byproducts, they still introduce THC into the body.
If you’re concerned, consult a fertility specialist and, of course, maintain a healthy diet and exercise regularly, as both improve fertility. But there are no safe ways to prevent THC-related damage.
“It’s best to quit smoking entirely,” said Hammadeh.
It’s important to note that many of these studies focus on chronic or high-dose marijuana use. However, due to potential impacts on fertility and overall health risks, caution is advised, and marijuana use should be avoided when trying to conceive or during pregnancy and breastfeeding.
If you have concerns about fertility and marijuana use, it’s best to speak with a doctor or fertility specialist for personalized advice.
