Cannabis Use and Male Fertility: Experts Sound the Alarm During Infertility Awareness Week
Male infertility contributes to approximately 45% of infertility cases among couples, according to data.
As National Infertility Awareness Week unfolds, experts are drawing attention to a growing concern: the potential negative impact of cannabis use on male reproductive health.
The Evidence on Cannabis and Sperm Quality
Heavy and chronic cannabis use has been directly linked to changes in reproductive hormones and semen parameters. A 2019 review published in The Journal of Urology found clear associations between cannabis use and reduced semen quality.
Perhaps most striking is a study of 1,215 healthy young Danish men, published in the American Journal of Epidemiology. The findings revealed that smoking cannabis more than once per week was associated with a 28% lower sperm concentration and a 29% lower total sperm count.
The risks escalate dramatically when cannabis is combined with other substances. Men who used cannabis alongside other recreational drugs more than once per week saw sperm concentration and count drop by 52% and 55%, respectively.
How Cannabis Affects Male Reproductive Function
Cannabis interacts with the body's endocannabinoid system, a complex network of receptors that plays a role in fertility. This interaction can impair sperm quality and reproductive function.
Research suggests cannabis can alter levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) —two critical hormones that support sperm production.
Expert Warnings
"Male infertility is common and under-evaluated."
— Dr. Stephanie Seminar, Chief of the Reproductive Endocrine Unit, Massachusetts General Hospital
Dr. Seminar explained that cannabis can cause changes in reproductive hormones and semen parameters, including decreased sperm counts or mobility. She noted that the drug can impact sperm quality, resulting in malformed sperm unable to swim effectively.
Good News: The Damage May Be Reversible
"Negative effects may be reversible when couples stop cannabis use."
— Dr. Alta DeRoo, Chief Medical Officer, Hazelden Betty Ford Foundation
Dr. DeRoo recommended discontinuing cannabis use at least three months before conceiving to allow the body to generate a full cycle of healthy sperm. This timeline is critical, as sperm production takes approximately 74 days.
Official Guidance
The American Society for Reproductive Medicine encourages couples trying to conceive to avoid recreational drugs to maximize chances of a healthy birth.
The Bigger Picture
The concern comes amid widespread cannabis use. In 2021, nearly one in five Americans (52.5 million people) used cannabis, making it the most common federally illegal drug in the country, per CDC data.
Recreational cannabis is now legal in roughly half of U.S. states, while medical marijuana is legal in well over 30 states—raising the stakes for public health education on its reproductive effects.