Does Marijuana Lower Sperm Count?

byMarcus Clarke3 minutes

Reports increasingly show that infertility rates in Canada are on the rise. Perhaps you or a cannabis-loving man in your life are concerned that marijuana consumption may be affecting sperm count and sperm health. We’ve all heard the stories about cannabis lowering sperm count. Are they fact or fiction? If Snoop Dogg has four kids and Willie Nelson has seven, can marijuana really contribute to a lower sperm count?

Everything You Need to Know About Sperm

Sperm is the male reproductive cell contained in semen that fertilizes a woman’s egg to make a baby. Sperm counts vary between men, with healthy men producing around 1.5–5 mL of semen every time they ejaculate. When healthy, sperm can live up to five days inside a woman’s reproductive tract.

Male infertility—due to low sperm count, poor sperm quality or undesirable sperm morphology (shape and size)— can bring on a lot of emotions including shock, disappointment and even guilt. Some of the factors that can cause male infertility include:

  • Genetics
  • Diet
  • Weight
  • Excessive alcohol and drug use
  • Stress
  • Age
  • Hormonal imbalances

Studies Show Cannabis Can Harm Sperm Health

A 2014 study on sperm samples in the UK showed that men aged 30 and younger who consumed marijuana regularly were twice as likely to have sperm with poor morphology. The abnormal size and shape of sperm may hinder its ability to fertilize an egg, although research was inconclusive as to why the sperm was affected by cannabis.


Another study suggests that marijuana reduces fertility by influencing hormones through the psychoactive cannabinoid tetrahydrocannabinol (THC). THC is thought to change several neural transmitters and lower gonadotropins in the body.

It’s the gonadotropins that are responsible for producing testosterone, and testosterone is instrumental in sperm production. THC also seems to supress thyroid gland function and the growth hormone, both of which may influence male reproduction. And the cannabinoid has also been found to hinder the ability of sperm to release enzymes, necessary for fertilizing an egg.

In 2015, a Danish study looked at the association between cannabis use, male reproductive hormones and semen quality. Of 1,215 men between the ages of 18 and 28, regular marijuana use resulted in 28% lower sperm concentration and 29% lower total sperm count. The men who reported marijuana consumption along with recreational drug use showed total sperm count reduced by 55%.

The good news is that lowered testosterone and sperm count resulting from the consumption of cannabis are wholly reversible. All men have to do is stop consuming cannabis, and sperm counts should return to normal. In fact, continued exposure to THC may even build up a tolerance to lowered testosterone and restore fertility.

Can Marijuana Treat Male Infertility?

In recent research, it seems cannabis may hold great potential in treating male infertility. Although marijuana—and specifically THC—adversely influences sperm mobility and count, the cannabinoid receptor CB2 may actually help regulate the creation of sperm.

Marijuana Moderation Is Key for a Healthy Sperm Count

Whether cannabis negatively or positively affects sperm count and sperm health seems to depend largely on the quantity of marijuana and ratios of cannabinoids consumed. As with most things in life, balance is key.

When activated, the body’s CB2 receptor plays a significant role in spermatogenesis, or the creation of sperm, and could help regulate and even boost sperm production. The tricky part is finding the correct strain of cannabis with the appropriate ratios of cannabinoids to activate that receptor. And since everyone’s endocannabinoid system is unique, what may work for one person may not necessarily work for another.

Further research is required to determine the use of cannabis in treating male infertility. So, if you’re actively trying to conceive or at all worried about your sperm count, it may be best to put away the cannabis and consult with a doctor about having a semen analysis.

Photo credit: Brooke Cagle