Marijuana use and its influence on sperm morphology and motility: identified risk for fertility among Jamaican men

The growing international movement legislating medical marijuana has brought renewed interest to the role of marijuana smoking on fertility potential. Although studies have identified that sperm quality can be compromised by marijuana use, little focus has been placed specifically on those trying to conceive. In this study, we aimed to clarify the impact of marijuana use in semen quality in men being investigated for assisted reproduction.

We conducted a cross-sectional study at a university-based facility in Jamaica. Routine semen analyses were performed on 229 men ages 23-72 years who were new clients. Logistic regression analyses were performed in order to independently predict quantifiable measures of the impact of marijuana use. The main outcome measures were sperm motility, total motile spermatozoa and morphology.

Overall, 47% of the participants reported marijuana use with 21% of these men reporting recent use. Regression analyses showed that recent use and users of large quantities of marijuana were 2.6 times (aOR = 2.6; 95% CI, 1.0-6.8, p = 0.044) and 4.3 times (aOR = 4.3; 95% CI, 1.1-15.9, p = 0.030) at greater risk of being diagnosed with abnormal motility (asthenozoospermia). Additionally, moderate quantity users were 3.4 times (aOR = 3.4; 95% CI, 1.5-7.9, p = 0.004) more likely to be diagnosed with abnormal morphology (teratozoospermia).

Recent use of marijuana as well as moderate to large quantities had an impact on sperm motility and morphology in men being investigated for infertility. We recommend therefore that men undergoing fertility investigations be routinely asked about their recreational use of marijuana and in particular recent and heavy users counselled to stop.