Certain activities, substances, or even physical environments can decrease male fertility by killing or damaging sperm cells.
If you’re trying to conceive with your partner, or if you think you might like to start a family someday, keep reading to learn more about how medical cannabis affects sperm count and fertility in men. Does cannabis affect sperm count and male fertility? Keep reading to find out!
Sperm Count, Morphology, and Motility: Causes of Male Infertility
Before we start this discussion, let’s clear up some important terminology: first and foremost, the difference between “sperm” and “semen.”
Semen, which contains sperm, is simply the fluid discharged during orgasm. You might hear it referred to as “seminal fluid.”
The sperm cells in semen – those tadpole-like cells you probably remember seeing pictures of in biology class – are what actually penetrate and fertilize egg cells (“ova”).
When we talk about a man’s overall “sperm quality,” we’re really talking about three distinct criteria:
- Sperm Count – “Sperm count” is the number of sperm cells in a given semen sample. Sperm count can range anywhere from about 15 million to 200 million sperm cells per milliliter of semen. A sperm count lower than 15 million sperm cells per milliliter is considered a low sperm count, a common condition known as “oligospermia.” A low sperm count can be increased, and does not necessarily make pregnancy impossible. However, oligospermia makes conceiving much more difficult.
- Sperm Morphology – Morphology is the study of physical structures and forms. Put simply, “sperm morphology” refers to normal versus abnormal sperm cells. A deformed sperm cell might be too large or too small, or be shaped abnormally (e.g. having two heads).
- Sperm Motility – Sperm cells have to be powerful swimmers in order to reach the egg. This ability to move around is called “motility.” Even if a man has a normal sperm count, abnormal sperm motility (or morphology) can still cause fertility problems.
In summary, there are three gauges of male fertility:
- How many sperm cells there are in a man’s semen (the count).
- How many of a man’s sperm cells are deformed (the morphology).
- How well a man’s sperm cells are able to swim around (the motility).
Does cannabis lower sperm count?
Now that we’ve clarified those critical terms, let’s take a closer look at how sperm quality might be impacted by cannabis use, based on peer-reviewed research conducted during the past decade.
Most research indicates that cannabis has negative effects on sperm and thus male fertility, which might be good or bad news depending on how soon you’d like to become a dad. Here are what some recent studies had to say on the subject of cannabis, sperm, and male fertility.
In 2015, the American Journal of Epidemiology published a study on “1,215 young Danish men aged 18 to 28 years.” Some of the men did not use cannabis, some used it weekly or less, and some used it more than once per week.
In the study, “Regular cannabis smoking more than once per week was associated with a 28% lower sperm concentration and a 29% lower total sperm count after adjustment for confounders.”
Additionally, “The combined use of cannabis more than once per week and other recreational drugs reduced the sperm concentration by 52% and total sperm count by 55%.” However, it’s impossible to know how much of this was attributable directly to cannabis, as opposed to the “other recreational drugs.”
The young age of the participants in the study is significant, because while men can have problems with sperm count, morphology, or motility at any age, these factors are more commonly seen in middle-aged or elderly men.
The Epidemiology study focused on sperm count and concentration of sperm cells, but did not examine motility or morphology. However, according to a 2011 study that was published in Frontiers in Bioscience, “[C]hronic exposure to delta-9-tetrahydrocannabinol [THC], the main psychoactive constituent of cannabis, impairs human reproductive potential by… reducing sperm count and motility.”
Similar effects have been noted in mice, with one 2012 study from the British Journal of Pharmacology finding, “Pretreatment of sperm for 15 min with 1 µM delta-9-THC reduced their basal motility and attenuated the ability of bicarbonate to stimulate flagellar beat frequency.” In other words, the British study showed that exposing sperm cells to THC decreased their motility, specifically by interfering with the process that normally prompts sperm cells to whip their tails at a certain frequency. (Interestingly, the same study mentioned that rimonabant – a banned drug that binds to the same receptors as cannabis, yet produces opposite effects – “has been shown to enhance sperm motility.”)
Cannabis could also have negative impacts on sperm morphology, meaning cannabis could cause more of your sperm cells to be shaped abnormally. Research published in Human Reproduction in 2014 established “use of [C]annabis in the three months prior to [semen] sample collection” as one of the “risk factors for poor sperm morphology,” even after adjusting for other factors, among men aged 30 or younger.
While older data is less valuable, the findings happen to be similar. For instance, a study that was published in 1985 in the Spanish medical journal Acta Ginecologica noted, “Declines in sperm volume and count and abnormal sperm motility have been observed in chronic cannabis users” (though the study did not define “chronic cannabis users”).
So, what’s the takeaway?
The bad news (if you want to become a father) is that cannabis appears to have negative effects on sperm count, sperm morphology, and sperm motility – all of which are important for getting pregnant.
The good news is that these effects aren’t permanent. Remember, these studies all looked at current or recent users of cannabis. If you’re worried about cannabis damaging your sperm quality or sperm count, try taking a break for a few months. And if that’s not an option, there are many other ways to try boosting your sperm count, ranging from advanced medical treatments to simple lifestyle changes.
Finally, it’s important to mention that, for men with initially normal sperm counts, the decrement likely with cannabis would not affect fertility.
The important thing is not to give up or get discouraged. Millions of couples have had perfectly healthy babies after struggling to conceive for months or even years.
The article is written by Dr. Jordan Tishler, the CEO of inhaleMD, a cannabis medicine clinic in Massachusetts. The article first appeared on inhaleMD’s website. Through his training in Internal Medicine and years of practice as an Emergency Physician, Dr. Tishler brings his knowledge, reason, and caring to patients at inhaleMD, and through his advocacy work at the local and national levels.