Is Marijuana Bad for Sperm and Male Fertility after a Vasectomy Reversal? 2023 Update

Yes, scientific research, just updated, confirms that marijuana users have lower sperm counts, sperm quality, semen volume and abnormal sperm DNA than men who do not use marijuana regularly.

This blog, about the impact of marijuana on sperm and male fertility is written by Dr. Sheldon Marks, based on research, published peer-reviewed scientific literature and expert opinion as presented at his colleagues at the University of Washington (1).

Everyone knows that marijuana is one of the most widely used drugs in the world. Now with legalization in 33 states in the US and many countries around the world for medical and recreational reasons, the use of marijuana is increasing, especially in young men before and during reproductive years. As with so many other products such as alcohol and tobacco, just because it is now legal does not mean it is safe for sperm.

The most common questions are “does marijuana use hurt sperm production or quality“? “How can marijuana impact on the ability to create and health of future children”? This is even more relevant for men who will be having or have had a vasectomy reversal and regularly use marijuana (2) as compared to “never users”(3)?

As with so many studies, there remains some controversy and the final definitive answer is still to be determined. As of the writing of this article, most experts would agree that the majority of research does show that regular and significant use of any cannabinoids hurts sperm and fertility in three ways (4).

First, most men that use marijuana regularly will have a drop in their testosterone levels. How much and for how long remains uncertain. In most situations when looking at the toxicity of any substance, the higher the dose, the more frequent the use and the longer the exposure (how many years was the drug used), the worse the impact of marijuana on testosterone production will be over time. Since a level of testosterone within the testicles is important for healthy sperm production, this is an area of concern. Usually, after marijuana is stopped, the testosterone levels are thought to return to normal levels, but can take time.

Second, significant use of a marijuana reduces a man’s sperm production. This could be from the drop in his testosterone and/or it may be from a direct effect of the cannabinoids on the cells in the testicles that make the sperm. Marijuana is estrogenic, which means it acts like estrogen in the cells. Since the balance of testosterone and estrogen in a man’s body is a critical for sperm production, any imbalance might explain why there are concerns about reduced sperm production.

Lastly, men exposed to significant amounts of marijuana over prolonged periods of time do show damage to the sperm, specifically the DNA, which carries the genetic code for future children. How long this lasts after marijuana is stopped is yet to be determined. Significant marijuana consumption, especially through smoking, can lead to higher levels of DNA fragmentation in the sperm which is associated increased risks for miscarriage and birth defects. Most importantly, the primary concern is how marijuana use might impact on the health of any children (5,6).

Since it takes about a month or more for the body to clear the metabolites of the marijuana, and then another 74 to 90 days for a new fresh cycle of sperm to be made, the earliest one could expect healthy sperm is about 4 months after stopping cannabinoids.

The key point is that like everything in life, there are potential risks to most everything, some more than others. It is important that each person consider and talk with their own doctors about the possible consequences to themselves and future children if they are a regular user of marijuana or CBD for personal or medical reasons.

Any questions on marijuana, CBD and sperm, male fertility or other vas reversal related subjects can be answered by either of our ICVR microsurgeons, Dr Sheldon Marks or Dr. Peter Burrows or our team of senior medical professionals.

This article was reviewed, updated and edited by Dr. Sheldon H F Marks on June 13, 2023.

References:
1. Cooper CA, Sloan MJ, Nicholson T, Hehemann MC, Raheem OA, Walsh T. Evaluation of the Impact of Marijuana Use on Semen Quality. AUA News. 01 Jan 2022.
2. Rossi BV, Abusief M, Missmer SA. Modifiable Risk Factors and Infertility: What are the Connections? Am J Lifestyle Med. 2014;10(4):220-231.
3. Hehemann MC, Raheem OA, Rajanahally S et al: Evaluation of the impact of marijuana use on semen quality: a prospective analysis. Ther Adv Urol 2021; 13:
4. Eisenberg ML. Invited Commentary: The Association between Marijuana Use and Male Reproductive Health.  2015 Am J Epidemiol 2015 Sep 15;182(6):482-4).
5. Gundersen TD, Jorgensen N, Andersson AM, Bang AK, Nordkap L, SkakkebaekNE, Priskorn L, Juul A, Jensen TK. Association between use of marijuana and male reproductive hormones and semen quality: a study among 1215 healthy young men. Am J Epidemiol 2015 Sep 15;182(6):473-81.
6. Lapham GT, Lee AK, Caldeiro RM et al: Frequency of cannabis use among primary care patients in Washington state. J Am Board Fam Med 2017; 30: 795.