From the Guidelines
Cannabis use by the male partner is not directly linked to birth defects in offspring, but it is recommended to stop or reduce use at least three months before conception as a precautionary measure. The current evidence on the impact of cannabis use on male fertility and birth defects is limited and inconclusive. According to the American Urological Association (AUA) and the American Society for Reproductive Medicine (ASRM) guideline part I 1, advanced paternal age is associated with increased de novo intra- and inter-genic germline mutations, sperm aneuploidy, structural chromosomal aberrations, sperm DNA fragmentation, birth defects, and genetically-mediated conditions in the offspring. However, there is no direct mention of cannabis use as a risk factor for birth defects in this guideline.
Some studies suggest that THC can affect sperm quality, count, and motility, but a clear causal link between paternal marijuana use and specific birth defects has not been established. The guideline mentions that ongoing use of anabolic steroids suppresses spermatogenesis and interferes with fertility, but it does not provide information on the effects of cannabis use on male fertility.
Key points to consider:
- Advanced paternal age is a known risk factor for birth defects and genetically-mediated conditions in the offspring 1
- There is limited evidence on the association between diet and male infertility, but a diet lower in fats and meats and higher in fruits and vegetables may be preferable 1
- Smoking has a small impact on sperm concentration, motility, and morphology, but the evidence is of low quality due to high risk of bias 1
- Men planning to conceive should consider stopping or reducing cannabis use at least three months before attempting conception as a precautionary measure, as THC can remain in the body for weeks and potentially affect developing sperm cells.
From the Research
Cannabis Use in Male Partners and Birth Defects
- The current evidence on the effects of cannabis use on reproductive health and birth defects is limited and conflicting 2.
- However, studies suggest that cannabis use may adversely affect male reproductive health, including lower sperm concentrations and altered sperm morphology 3, 4, 5.
- Cannabis use has been reported to disrupt the hypothalamic-pituitary-gonadal axis, spermatogenesis, and sperm function, which may lead to fertility issues and potentially increase the risk of birth defects 6, 4.
- One study found that infertile men who used cannabis were at higher risk of having lower testosterone levels and altered sperm morphology, including teratozoospermia (abnormal sperm shape) 5.
- While there is no direct evidence linking cannabis use in male partners to birth defects, the available data suggest that cannabis use may have negative effects on reproductive health and fertility, which could potentially increase the risk of birth defects 2, 3, 6, 4, 5.