Having a child is a milestone for many couples around the world – including those that consume cannabis. Fertility involves a number of factors, taking into consideration the health of both the female and male that are trying to conceive. A common question people have is whether cannabis consumption can also be added to the list of factors that may impact an individual's ability to become pregnant. So really, can smoking cannabis affect fertility?
The short answer is maybe. Unfortunately, the research on marijuana and fertility is inconsistent at best. Newer research is being released, but has not been conclusive yet. However, most of THC's effects can be seen in endocannabinoid system that is already being studied.
The endocannabinoid system interacts with THC and is what makes you feel high, but the system is also in place for other reasons. Endocannabinoids and cannabinoid receptors act as a regulatory system for the human body and are found in cells throughout the body. This system is partly why cannabis can have an impact on fertility, as there are cannabinoid receptors in our reproductive systems.
Cannabis use can particularly impact – both positively and negatively – the regular functions of the system. Cannabis may have impacts beyond this system, so it's important to understand how bodies are truly affected by the consumption of the cannabis.
Can Smoking Cannabis Affect Fertility in Men?
Male fertility is based on several factors, like hormonal imbalances, medications, overheating of testicles and more. And smoking cannabis can be yet another factor that affects sperm count. In one of the larger studies conducted on male fertility, researchers found several key results. Among 1,215 young males in the sample, 45% had smoked marijuana in the last three months. For those that regularly consume marijuana, sperm counts and sperm concentration were all significantly reduced by 28% and 29%, respectively.
Researchers also found that marijuana consumers that consumed another recreational drug in addition to marijuana, had reduced counts and concentration by 52% and 55%. Though consuming only marijuana did not correlate with with a huge drop in sperm count and concentration, this study shows that there could be some impact.
In a few other studies, researchers have focused on the binding of cannabinoids to sperm receptors. These sperm receptors, CB1 and CB2, are susceptible to THC in the system. Both studies found that marijuana use caused the receptors to significantly decrease the motility of sperm. Motility essentially refers to a sperm's ability to swim fast enough at the right time in order to reach the egg before burning out. If a sperm fails to have the right motility, the egg will fail to be fertilized.
Though many of these studies were not been conducted in the last eight years, they still can show a reflection of how it may be true that smoking cannabis can affect fertility.
Can Smoking Cannabis Affect Fertility in Women?
While smoking cannabis may affect sperm count in males, it can also affect several key areas in the female body as well. When it comes to fertility, a woman's menstrual cycle is one of the most important factors in trying to conceive. In a 2016 study, results suggest that cannabis consumption can disrupt the regular menstrual cycle and the release of the egg from the ovaries. The report cites that there was an increased rate of anovulatory cycles, meaning no ovulation would occur. This is crucial, because without the regular release of an egg during ovulation, there is a much smaller chance of becoming pregnant. Another study found that occasional marijuana use results in delayed ovulation.
It's important to note that these studies had fairly small sample sizes, and may not be entirely reflective of cannabis and its effect on fertility.
It's also important to note the effect on the endocannabinoid system in reference to the female reproductive system. In a more recent report, researchers explain that cannabinoid receptors are found in the ovaries and fallopian tubes. When the intake of cannabis activates the receptors there, it disrupts the normal functions in the reproductive system. If these normal functions are being neglected due to consumption of THC, women may be more likely to have reduced fertility, ectopic pregnancies or spontaneous abortions. Again, note that these studies are based on small samples or have been conducted on animals – not humans.
Research Is Contradictory
While previous research supports the notion that smoking cannabis can affect fertility, other studies have found evidence that contradicts those conclusions. In a survey conducted several times in the last decade, researchers looked at the frequency of cannabis use among the sample. Of 758 males and 1,076 females actively trying to conceive, 16.5% of males and 11.5% of females reported using cannabis during that time.
Results concluded that cannabis use or frequency of use had no association among time getting pregnant between couples. Rates of marijuana use were low among the sample size, but these results display cannabis had no effect on fertility.
Another recent study utilized online pregnancy questionnaires to determine cannabis consumption among participants (both female and male partners). The analysis totaled 4,194 women, including 1,125 male counterparts that completed the questions. Follow-up questions continued until a woman or couple had become pregnant, initiated fertility treatment, or failed to follow-up. The study found that men were more likely to be marijuana consumers than women, but ultimately concluded that there was little association between cannabis consumption and decreased fertility.
This study is fairly relevant as it had the highest sample size of real couples with women trying to conceive. Though external variables could not necessarily be controlled, results are comparable to the other previous study.
Conclusions on Cannabis and Fertility
With research supporting both sides, it can be hard to answer the question, “Can smoking cannabis affect fertility?” With a lack of research on humans (many older studies were conducted on rats), it can be difficult to conclude what effects cannabis has on the reproductive system. With legalization building steam, it is likely more people will consume cannabis in the next following years. Academics should be encouraged to pursue more in-depth studies on how cannabis can affect fertility. By increasing sample sizes and involvement, future research may be able to point us in a clearer direction.
In the meantime, consuming cannabis while trying to conceive seems to be a personal choice. Many women choose to use cannabis to relieve pain and cramping during their menstrual cycles by using topical creams or oils. Many people use marijuana for health reasons, relaxation, or as a sleep aid. Because cannabis consumption is a personal preference, men and women should evaluate whether they want to pursue having a child while also consuming the substance.
Currently, the American College of Gynecologists and Obstetricians advise women to stay away from cannabis before or during pregnancy. If smoking is essential to other health issues or lifestyles, doctors and fertility specialists are still the best place to look for information. Until more research is conducted, we may not truly know how fertility is being altered by cannabis use.