THC detected in human semen for the first time

In the first study to measure THC in human semen, researchers detected the compound in some chronic cannabis users, showing THC can cross the blood-testis barrier.

Lee, Malinda S et al.·Journal of assisted reproduction and genetics·2020·Preliminary EvidencePilot Study
RTHC-02680Pilot StudyPreliminary Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Pilot Study
Evidence
Preliminary Evidence
Sample
N=12

What This Study Found

Among 12 heavy cannabis users, THC was detectable above reporting levels (0.50 ng/mL) in 2 of 10 analyzable semen samples. Seminal THC was moderately correlated with serum THC levels (r=0.66). Notably, semen parameters (concentration, motility, morphology) were within normal ranges despite heavy cannabis use, though prolactin was elevated in half the participants.

Key Numbers

12 participants; THC detected in semen of 2/10 samples; moderate correlation with serum THC (r=0.66); median sperm concentration 75.5M/mL, motility 69.5%, morphology 5.5% (all normal); prolactin elevated in 6/12.

How They Did This

Proof-of-concept study with 12 healthy men aged 18-45 who were chronic heavy users of inhaled cannabis. THC and metabolites measured in serum, urine, and semen using LC-MS/MS. Standard semen analysis performed.

Why This Research Matters

This is the first demonstration that THC crosses the blood-testis barrier in humans. This has implications for understanding potential effects on sperm function and reproductive outcomes.

The Bigger Picture

If THC is present in the reproductive tract, it could potentially affect sperm function or early embryo development. This proof-of-concept opens a new area of investigation in reproductive toxicology.

What This Study Doesn't Tell Us

Very small sample (n=12, only 10 analyzable); THC only detectable above threshold in 2 samples; no comparison with non-users; single time point; cannot determine functional significance of seminal THC.

Questions This Raises

  • ?Does seminal THC affect sperm function or fertilization?
  • ?Could THC in semen affect embryo development?

Trust & Context

Key Stat:
First detection of THC in human semen; correlated with blood levels (r=0.66)
Evidence Grade:
Preliminary: very small proof-of-concept study; THC only detected in 2 of 10 samples.
Study Age:
Published 2020.
Original Title:
Delta-9 THC can be detected and quantified in the semen of men who are chronic users of inhaled cannabis.
Published In:
Journal of assisted reproduction and genetics, 37(6), 1497-1504 (2020)
Database ID:
RTHC-02680

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A small preliminary study to test whether a larger study is feasible.

What do these levels mean? →

Frequently Asked Questions

Does cannabis affect semen quality?

In this small study of 12 heavy users, semen parameters (concentration, motility, morphology) were within normal ranges. However, THC was detected in some semen samples, and half the participants had elevated prolactin.

What does THC in semen mean for fertility?

The functional significance is unknown. This study only demonstrated that THC can cross the blood-testis barrier. Whether it affects sperm function or fertility requires further research.

Read More on RethinkTHC

Cite This Study

RTHC-02680·https://rethinkthc.com/research/RTHC-02680

APA

Lee, Malinda S; Lanes, Andrea; Ginsburg, Elizabeth S; Fox, Janis H. (2020). Delta-9 THC can be detected and quantified in the semen of men who are chronic users of inhaled cannabis.. Journal of assisted reproduction and genetics, 37(6), 1497-1504. https://doi.org/10.1007/s10815-020-01762-1

MLA

Lee, Malinda S, et al. "Delta-9 THC can be detected and quantified in the semen of men who are chronic users of inhaled cannabis.." Journal of assisted reproduction and genetics, 2020. https://doi.org/10.1007/s10815-020-01762-1

RethinkTHC

RethinkTHC Research Database. "Delta-9 THC can be detected and quantified in the semen of m..." RTHC-02680. Retrieved from https://rethinkthc.com/research/lee-2020-delta9-thc-can-be

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.