Dr Raha: The general advice to clinicians from the Society of Obstetricians and Gynecologists of Canada is to avoid exposure to cannabis during pregnancy, although there is the potential that when there is lifelong exposure, fertility could already be compromised. However, I caution that systematic studies elucidating the mechanisms behind altered fertility in both males and females are lacking. So, my advice to clinicians would be to recommend avoiding the use of cannabis products during pregnancy, and to increase vigilance in monitoring a pregnancy if a couple has used cannabis products in the recent past, before becoming pregnant.
Endocrinology Advisor: What are additional clinical considerations pertaining to cannabis use in patients of reproductive age?
Dr Ilnitsky: As marijuana use for medical indications increases and more states and countries legalize the drug, it becomes more and more important to ask about and address its use with our patients. When a patient is using medical marijuana, the risks and benefits of continuing use while trying to conceive and into pregnancy need to be discussed. It is also important to know that we have little to no information about the effects of other popular marijuana-based products such as edibles and cannabidiol oil.
Dr Clavijo: Clinicians should be aware that research on how cannabis affects fertility is very scant, and most of it is more than 2 decades old. It is important to realize that cannabis comes in many forms and can be consumed in many ways. On top of that, there are hundreds of strains with different concentrations of different cannabinoids. Given this, pending results of contemporary high-quality studies isolating individual components of cannabis, no definitive conclusions can be made regarding the effect of cannabis on fertility potential.
Endocrinology Advisor: What do you see as the most pressing needs in this area in terms of research or education?
Dr Ilnitsky: Unfortunately, all the studies conducted thus far are relatively small or are population-based studies with inherent confounders. All aspects of marijuana’s effects on fertility and early pregnancy require further study. Although it will be challenging, the increasing prevalence of marijuana use will provide more opportunities to perform high-quality research.
It is also important to educate patients about what we do and do not know about marijuana’s effects. Again, clinicians should ask about and address marijuana use the way they do tobacco and alcohol use. Public education would be difficult at this point, as we do not have strong definitive evidence of an effect.
Dr Clavijo: First, more funding needs to be available to conduct high-quality, ideally randomized controlled studies using individual well-characterized cannabis strains or their individual cannabinoid components. This will allow us to have an idea as to what the possible molecular mechanisms are or at least how to begin to elucidate them. To be taken more seriously, the cannabis industry also needs to do their part and start setting quality standards, particularly for cannabis meant to treat medical conditions.
1. Brents LK. Marijuana, the endocannabinoid system and the female reproductive system. Yale J Biol Med. 2016;89(2):175-191.
2. du Plessis SS, Agarwal A, Syriac A. Marijuana, phytocannabinoids, the endocannabinoid system, and male fertility. J Assist Reprod Genet. 2015;32(11):1575-1588.
3. Gundersen TD, Jørgensen N, Andersson AM, et al. Association between use of marijuana and male reproductive hormones and semen quality: a study among 1,215 healthy young men. Am J Epidemiol. 2015;182(6):473-481.
4. Jukic AMZ, Weinberg CR, Baird DD, Wilcox AJ. Life-style and reproductive factors associated with follicular phase length. J Womens Health (Larchmt). 2007;16(9):1340-1347.
5. Kasman AM, Thoma ME, McLain AC, Eisenberg ML. Association between use of marijuana and time to pregnancy in men and women : findings from the National Survey of Family Growth. Fertil Steril. 2018;109:866-871.
7. Walker OS, Holloway AC, Raha S. The role of the endocannabinoid system in female reproductive tissues. J Ovarian Res. 2019;12(3).
This article originally appeared on Endocrinology Advisor