Medically Reviewed by
Jason Crawford

Article Last Updated on January 13, 2023

As recreational marijuana is slowly being destigmatized with the legalization laws in the United States, cannabis use is likely to go up, especially among young people who are of reproductive age. 

While smoking pot may be a way for you to decrease tension after a stressful day at work, or a social thing between you and your friends on a Saturday night, it might affect your fertility. No matter what the circumstances for marijuana consumption may be, recent studies show that the effects of marijuana on human reproduction may be substantial.

So, let’s dive into the article in order to answer the question that’s probably on your mind – Can marijuana use influence our reproductive health to the point that it causes fertility problems?        

The Endocannabinoid System vs the Reproductive System

Human reproduction is the way our species has managed to evolve and thrive, thanks to the proper function of our reproductive system. The reproductive system is the biological system that unites all of the anatomical organs, hormones, fluids, and pheromones that are involved in human reproduction. Since it has such an important role, we need to take care of it in order for it to function properly.

On the other hand, the endocannabinoid system (ECS) is a complex cell-signaling system that’s composed of endocannabinoids, cannabinoid receptors, and various endocannabinoid metabolic enzymes. Its main function is to maintain homeostasis (balance the body out). Apart from endocannabinoids, cannabinoids like tetrahydrocannabinol (THC), cannabidiol (CBD), and other cannabinoids found in weed affect this system.

The interconnection between the endocannabinoid system and the reproductive system hasn’t been fully researched yet, although more and more studies are done that explore this subject.

Can Smoking Marijuana Cause Infertility?

A paper published in the Canadian Medical Association Journal by Sara Ilnitsky and co-author Stan Van Uum dived into the subject of marijuana and fertility. The five main points of the paper are listed as follows.

  • “Tetrahydrocannabinol acts on the endocannabinoid system, which is ubiquitous in reproductive tissues; 
  • Marijuana use can decrease sperm count;
  • Marijuana use may delay or inhibit ovulation;
  • For most couples, smoking marijuana does not affect their ability to conceive, but for couples with infertility problems, it could be a contributing factor.”

More and better-quality research is needed concerning the fertility implications of recreational marijuana use.           

The endocannabinoid system has an important role in gametogenesis, implantation, and early pregnancy according to this study by the University of Leicester. Since THC affects the ECS, it might be problematic for marijuana users to get pregnant.

Cannabis and Sperm Count

When we look into male fertility, the main thing scientists look at is sperm health, which is defined by sperm count and sperm motility. Men who have a higher sperm count are more likely to conceive compared to men who have a lower count.

Recent studies like this 2015 one, point that regular marijuana users have 29 percent lower sperm counts compared to men who didn’t use marijuana.

Based on studies that show how heavy use of cannabis affects sperm count, increases sperm malformation, and decreases sperm motility, doctors advise against cannabis for men who are trying to conceive. 

Cannabis and Ovulation

We already know that pregnant and breastfeeding mothers should avoid marijuana at all costs since cannabis can enter the placenta and potentially harm the baby. Compared to men, it’s harder to study the effect of marijuana on women’s fertility because there’s not an adequate measure to look at as there is with semen. Although, when it comes to female fertility, the first thing that’s researched is the menstrual cycle. 

Studies like the one done by Research Triangle Park in North Carolina, show that the effects of marijuana may result in an ovulatory delay or inhibition in women. Another study showed that women who use both marijuana and tobacco may have a shorter luteal phase compared to women who only use tobacco.

A study researching the use of marijuana and how it affects couples doing fertility treatments with in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT), showed that marijuana use negatively affected IVF/GIFT

Moreover, the production of estrogen is of vital importance when it comes to ovulation, and high amounts of THC can decrease estrogen production. Since ovulation is essential for the possibility of conceiving, if it doesn’t happen, the egg won’t be released from the fallopian tube, and there will be no chance for a pregnancy.

Cannabis Use and Genetic Modifications

Marijuana research has only scratched the surface as more and more studies are looking into the health effects that might come from marijuana consumption as well as the medical conditions that might be aggravated.

When looking into this 2019 study, we find out that marijuana use in men is associated with changes in the gene Discs-Large Associated Protein 2 (DLGAP2) that is associated with autism. The study showed that the DLGAP2 gene underwent methylation in men who smoke or ingest marijuana. This gene is associated with autism, but also with schizophrenia and post-traumatic stress disorder.

Even though this is one of the first studies of its kind, more research needs to be done on the subject. In any case, it’s better to be safe than sorry. 

Final Thoughts on Marijuana and Fertility

Scientists don’t have a definitive opinion when it comes to the connection between the use of marijuana and fertility, given that this is an area which hasn’t been thoroughly researched. More studies are needed in order for healthcare professionals to be able to provide definitive guidelines concerning cannabis and fertility.

For now, the best option you have is to stay away from marijuana as you and your partner are trying to get pregnant, especially if you’re doing infertility treatments. This way you’ll be on the safe side when it comes to the health of your future child.

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.