THC and CBD May Have Opposing Effects on Male Fertility | Research

The takeaway

A review of the literature found growing evidence that THC negatively affects sperm quality, hormones, and epigenetics, while CBD may have protective effects on male reproductive health through anti-inflammatory and antioxidant pathways.

Men considering cannabis use who are planning families, fertility specialists, and reproductive health researchers.

What the researchers found

THC has been associated with reduced sperm quality, altered hormone levels, and changes in genetic and epigenetic profiles. CBD, conversely, may exert protective effects on male reproductive health through its anti-inflammatory and antioxidant properties, though evidence remains limited.

Why it matters

Cannabis use is common among men of reproductive age, yet most research has focused on THC's harms without considering whether CBD might offset some of these effects. As CBD-dominant products become more popular, understanding these potentially opposing effects is important for reproductive counseling.

The numbers in context

No pooled quantitative data; this is a narrative review synthesizing findings across multiple studies on THC and CBD effects on male reproductive parameters.

How the study worked

Narrative review of published literature on the mechanisms by which THC and CBD influence male reproductive health, including effects on sperm parameters, hormone levels, and genetic/epigenetic markers.

What this study cannot tell us

Narrative review without systematic search or meta-analysis. Most underlying studies were animal or in vitro, with limited human data. CBD research on male fertility is still in early stages. Cannot account for the effects of whole-plant cannabis with both compounds present.

How to read the evidence

Narrative review drawing on mostly animal and in vitro studies. The THC harm signal is more established; CBD's protective role is still emerging and speculative.

When this study was published

Published 2025, reviewing literature through 2024.

The bigger picture

The distinction between THC and CBD effects on fertility mirrors their divergent profiles across other health domains. If confirmed, this opposition could have implications for product recommendations: whole-plant cannabis with both THC and CBD might affect fertility differently than THC-only or CBD-only products.

Questions still open

Whether CBD can actually reverse THC-induced reproductive harm when both are consumed together
What threshold of THC exposure poses meaningful fertility risk in humans

Common questions

Should men trying to conceive avoid cannabis?

The evidence on THC and sperm quality is concerning, though not definitive in humans. The review suggests THC may impair multiple aspects of male fertility, while CBD's role is still unclear. Men concerned about fertility should be aware of these findings.

Does CBD actually protect sperm?

Some laboratory and animal studies suggest CBD has anti-inflammatory and antioxidant properties that could benefit reproductive cells. However, direct evidence of CBD protecting human sperm or improving male fertility outcomes is still lacking.

Read the original research

Do Delta-9-tetrahydrocannabinol and Cannabidiol have opposed effects on male fertility?

Toxicology letters, 403, 94-104

View on PubMed ↗Publisher’s paper ↗

Citation

Scandlan, Olivia L M; Favetta, Laura A. (2025). Do Delta-9-tetrahydrocannabinol and Cannabidiol have opposed effects on male fertility?. Toxicology letters, 403, 94-104. https://doi.org/10.1016/j.toxlet.2024.12.003