Cannabis for Male Reproductive Issues

Overseen By Carrie Cuttler, PhD

Age: 18 - 65

Sex: Male

Trial Phase: Phase 1

Sponsor: Kanako Hayashi

Must not be taking: Corticosteroids, Blood thinners

Disqualifiers: Women, Psychiatric conditions, Heart disease, others

Compensation: Varies

Number of Visits: 2

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how cannabis affects male reproductive health, focusing on sperm count and testosterone levels. Participants will be divided into groups to test different scenarios: no cannabis, placebo (fake cannabis), and two doses of cannabis (20mg and 40mg THC). Men aged 21-64 who regularly use cannabis (at least once a week for a year) and can abstain for five hours before testing may be suitable candidates. Participants will provide surveys, blood samples, and semen samples for this research. As a Phase 1 trial, the research focuses on understanding how the treatment works in people, offering participants the chance to contribute to this groundbreaking study.

Will I have to stop taking my current medications?

The trial requires that participants stop using corticosteroids and blood thinners. If you are taking these medications, you will need to stop before participating.

Is there any evidence suggesting that this treatment is likely to be safe for humans?

Research shows that cannabis, especially THC, can impact male reproductive health. Some studies have found that cannabis use might lower sperm count, resulting in fewer sperm in users compared to non-users. However, other research has not found strong links between cannabis use and changes in male fertility, except for a slight increase in a hormone called FSH, which is involved in reproduction.

While these findings suggest possible effects, detailed safety information on how THC affects male fertility remains limited. Some experts believe that stopping THC use might reverse its negative effects on fertility. Overall, these studies advise caution but do not provide a complete picture of cannabis's safety regarding male reproductive health. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about using cannabis for male reproductive issues because it offers a novel approach compared to traditional treatments like hormone therapy or surgical interventions. Unlike other treatments that may focus on altering hormone levels or repairing physical structures, cannabis works by interacting with the endocannabinoid system, which could influence sperm production and function. The study specifically looks at different doses of THC, the active ingredient in cannabis, which may offer insights into its optimal use and efficacy. This could lead to more personalized treatment options with potentially fewer side effects.

What evidence suggests that cannabis might be an effective treatment for male reproductive issues?

This trial will explore the effects of cannabis on male reproductive health. Research has shown that cannabis use can affect men's reproductive health. Studies have found that cannabis might lower sperm count and concentration, alter sperm shape, and reduce sperm movement. THC, the main active ingredient in cannabis, has been linked to changes in hormone levels and can cause the testes to shrink. However, some evidence suggests that stopping THC use might reverse these effects. While cannabis might impact fertility, the exact effects can vary, and more research is needed to fully understand them. Participants in this trial will be divided into different groups, including non-cannabis users and cannabis users with varying THC dosages, to assess these potential impacts. ^{1 2 3 4 5}

Who Is on the Research Team?

Kanako Hayashi, PhD

Principal Investigator

Washington State University

Are You a Good Fit for This Trial?

This trial is for men with substance use disorder and reproductive issues. Participants must be cannabis users or non-users willing to provide blood and semen samples, as well as complete surveys on their cannabis use and sexual health.

Inclusion Criteria

I am a man aged 21-64 who uses cannabis weekly or have never used it.

Willingness to abstain from using cannabis on the day of the testing session (minimum 5 hours abstinence)

Exclusion Criteria

Family history of psychosis

I am a woman.

BMI over 34

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are exposed to cannabis or placebo via the Volcano Vaporizer, with assessments of reproductive parameters

1 day

1 visit (in-person)

Acute Monitoring

Participants undergo acute stress testing and monitoring of plasma cortisol and food intake

4 hours

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Cannabis

Trial Overview

The study tests the effects of different doses of THC in cannabis (0mg, 20mg, 40mg) on male reproductive functions like sperm count and testosterone levels. It's a double-blind trial where participants won't know if they're getting THC or a placebo.

How Is the Trial Designed?

Group I: non-cannabis users Active Control 1 Intervention

Non-cannabis users (n=20) will be assigned to a non-vaping group.

Group II: Cannabis users: non-vaping Active Control 1 Intervention

Cannabis users (n=20) will be assigned to a non-vaping group.

Group III: Cannabis users: 20mg THC in cannabis plant Active Control 1 Intervention

Cannabis users (n=20) will be assigned to a 20mg THC in cannabis group.

Group IV: Cannabis users: 40mg THC in cannabis plant Active Control 1 Intervention

Cannabis users (n=20) will be assigned to a 40mg THC group.

Group V: Cannabis users: placebo Placebo Group 1 Intervention

Cannabis users (n=20) will be assigned to a placebo group.

Who Is Running the Clinical Trial?

Kanako Hayashi

Lead Sponsor

Trials

1

Recruited

100+

Washington State University

Collaborator

Trials

114

Recruited

58,800+

Citations

1.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC7385722/

Cannabis and Male Fertility: A Systematic Review - PMC

Research supports a role for cannabis in reducing sperm count and concentration, inducing abnormalities in sperm morphology, reducing sperm motility and ...

2.

nature.com

nature.com/articles/s41598-025-91894-0

Effects of marijuana and tobacco on male fertility and their ...

Gundersen et al., documented a significant decrease in sperm concentration among cannabis users compared to non-users52.

3.

sciencedirect.com

sciencedirect.com/science/article/pii/S0890623825001753

Ever cannabis use and biomarkers of male fecundity

We hypothesized that ever cannabis use is associated with lower semen quality and changes in reproductive hormone levels. 2. Methods. 2.1. Study population.

4.

news.ohsu.edu

news.ohsu.edu/2023/03/27/ending-thc-use-may-reverse-negative-impacts-on-male-fertility

Ending THC use may reverse negative impacts on male ...

Analyses showed that THC exposure caused a significant reduction in size of the testes and impacted male productive hormones, both which ...

5.

asrm.org

asrm.org/practice-guidance/practice-committee-documents/tobacco-or-marijuana-use/

Tobacco or marijuana use and infertility: a committee opinion

Marijuana use has not been consistently associated with male or female fecundity, time to pregnancy, reproductive hormone levels, semen parameters, or ART ...