What are the effects of cannabis use on fertility and reproductive health in individuals trying to conceive?

Cannabis Use While Trying to Conceive

Individuals trying to conceive should completely abstain from all cannabis/THC use, as current evidence demonstrates detrimental effects on both male and female fertility, sperm quality, reproductive hormones, and pregnancy outcomes. 1, 2

Recommendation for Both Partners

Complete cessation of cannabis use is strongly recommended for all individuals attempting conception, based on documented reproductive toxicity across multiple organ systems and reproductive functions. 1, 3

• The American College of Obstetricians and Gynecologists explicitly recommends that people who are pregnant, trying to become pregnant, or breastfeeding abstain from using cannabis. 3
• WHO guidelines on male infertility strongly recommend men trying for pregnancy abstain from recreational drugs including marijuana, as these substances adversely affect semen quality and fertility. 1

Impact on Male Fertility

Documented Effects on Sperm Parameters

Cannabis use is associated with multiple detrimental effects on male reproductive function:

• Most studies demonstrate lower sperm concentrations in cannabis users, suggesting negative impact on fertility potential. 1
• Cannabis disrupts the hypothalamic-pituitary-gonadal axis, affecting testosterone production and reproductive function. 1, 4
• Male cannabis use is associated with erectile dysfunction, abnormal spermatogenesis, and testicular atrophy. 2
• The endocannabinoid system plays a critical role in regulating spermatogenesis, sperm motility, capacitation, and the acrosome reaction—all of which can be disrupted by exogenous cannabinoids. 4

Clinical Evaluation for Male Partners

When evaluating men with fertility concerns who use cannabis:

• Obtain comprehensive substance use history including frequency, duration, and quantity of marijuana use during initial fertility assessment. 1
• Perform standard semen analysis assessing multiple parameters (concentration, motility, morphology) rather than single measurements. 1, 3
• Consider repeat semen analysis if abnormalities are detected, as assessment of multiple ejaculates provides better predictive value. 1, 3
• Men with already compromised semen parameters, recent users, and moderate-to-heavy quantity users require particular emphasis on complete cessation. 1

Impact on Female Fertility

Reproductive System Effects

Cannabis use disrupts multiple aspects of female reproductive health:

• Cannabinoid receptors are present throughout the female reproductive tract, indicating the endocannabinoid system's regulatory role in reproduction. 2
• Cannabis use is associated with altered reproductive hormones and menstrual cyclicity. 2
• Female cannabis users experience infertility and abnormal embryo implantation and development. 2
• Exogenous cannabinoids interfere with the endocannabinoid system and disrupt the hypothalamic-pituitary-ovary axis, impacting normal secretion of ovarian sex hormones and menstrual cycles. 5

Pregnancy and Offspring Risks

Cannabis use during pregnancy carries significant risks that extend beyond conception:

• Delta-9-tetrahydrocannabinol (THC) crosses the placenta and has been detected in breast milk. 2
• Maternal cannabis use is associated with low birthweight, small-for-gestational-age infants, and preterm birth. 3, 2
• Cannabis smoking during pregnancy is specifically associated with low birthweight. 3
• Fetal neurodevelopmental consequences and impaired offspring sociobehavioral and cognitive development are documented. 2
• Cannabis use may negatively affect fetal brain development and increase risk for premature birth. 6

Patient Counseling Strategy

Key Counseling Points

Healthcare providers should directly address cannabis use with all patients attempting conception:

• Only 9.4% of past-year cannabis users reported their healthcare provider instructed them to discontinue use, representing a critical counseling gap. 7
• Among infertility patients, 13% used cannabis within the past year, similar to general population rates. 7
• Past-year cannabis users perceive less negative effect on fertility and pregnancy compared to non-users, indicating a dangerous knowledge gap. 7
• Tobacco, alcohol, and drug use can affect spermatogenesis, and men should be counseled about these factors during wellness visits. 3

Specific Populations Requiring Emphasis

Prioritize counseling for:

• Men with already compromised semen parameters who use cannabis. 1
• Recent users and those with moderate-to-heavy quantity consumption patterns. 1
• Women of reproductive age, as cannabis use is increasing in this population despite known risks. 2, 8
• Both partners in couples with unexplained infertility. 3

Critical Caveats

Important considerations for clinical practice:

• The potency of cannabis products has increased dramatically, with average THC concentration almost doubling from 9% in 2008 to 17% in 2017, and cannabis concentrates may contain THC levels as high as 70%. 6
• Large-scale prospective trials examining recreational drug effects on actual fertility outcomes (pregnancy rates, live births) are still needed, though consistent findings across multiple studies regarding semen parameter deterioration justify the precautionary recommendation for complete abstinence. 1
• The prevalence of cannabis use among infertility patients (13%) mirrors general population rates, suggesting many patients do not recognize or act on fertility risks. 7
• Secondhand smoke exposure from a partner can also lead to low birth weight, intrauterine growth restriction, and preterm birth. 3