What are the effects of maternal Tetrahydrocannabinol (THC) use on children?

From the Guidelines

Maternal THC use during pregnancy can have severe and long-lasting negative effects on children's development, and women should avoid using cannabis products containing THC while pregnant or breastfeeding. THC (tetrahydrocannabinol), the psychoactive component in marijuana, crosses the placenta and can enter breast milk, directly affecting the developing fetus and infant. Research indicates that prenatal THC exposure may lead to lower birth weight, attention problems, decreased cognitive function, and increased risk of behavioral issues in children, as stated in the position paper from the American College of Physicians 1. These effects occur because THC interferes with the endocannabinoid system, which plays a crucial role in fetal brain development, particularly in forming neural connections and establishing normal brain architecture. Some studies suggest that these effects may persist into adolescence, potentially affecting academic performance and social adjustment. The developing brain is particularly vulnerable to external substances, and THC's lipophilic properties allow it to accumulate in fetal tissue. Even occasional use during pregnancy may pose risks, as there is no established safe threshold for THC exposure during fetal development. The U.S. Surgeon General and the FDA advise pregnant and breastfeeding people to avoid using cannabis in any form, including CBD products, due to the potential negative effects on fetal brain development and increased risk for premature birth 1.

Key points to consider:

• Maternal THC use can lead to lower birth weight and increased risk of premature birth
• Prenatal THC exposure may cause attention problems, decreased cognitive function, and increased risk of behavioral issues in children
• The effects of THC on fetal brain development can persist into adolescence, affecting academic performance and social adjustment
• There is no established safe threshold for THC exposure during fetal development, and even occasional use during pregnancy may pose risks
• The U.S. Surgeon General and the FDA advise pregnant and breastfeeding people to avoid using cannabis in any form, including CBD products.

It is essential to prioritize the health and well-being of both the mother and the child, and avoiding THC use during pregnancy and breastfeeding is crucial to minimize potential harm. As stated in the most recent study from 2024, the potential risks associated with maternal THC use outweigh any potential benefits, and women should be advised to avoid using cannabis products containing THC while pregnant or breastfeeding 1.

From the Research

Effects of Maternal Tetrahydrocannabinol (THC) Use on Children

• Maternal THC use during pregnancy has been associated with an increased risk of fetal growth restriction and adverse neurodevelopmental consequences 2.
• Studies have also shown that maternal cannabis use during pregnancy is associated with small to moderately increased risks of gestational hypertension, gestational weight gain less than or greater than guidelines, and placental abruption 3.
• Additionally, maternal cannabis use during pregnancy has been linked to an increased risk of preterm birth, small for gestational age, low birth weight, neonatal intensive care unit admission, and fetal death 3.
• The risk of these adverse outcomes is greater with greater frequency of cannabis use, and these risks have been identified even in women who do not use other substances during pregnancy 3.

Breastfeeding and THC Exposure

• Women who use cannabis during lactation place their infants at risk of exposure to cannabis and its metabolites in breast milk 4.
• It is recommended that women abstain from cannabis use during lactation or reduce consumption if abstinence is not possible, and avoid breastfeeding within 1 hour of inhaled use to reduce exposure to the highest concentration of cannabis in breast milk 4.
• However, further research is needed to determine the impact of post-natal exposure to cannabis on infant neurodevelopmental outcomes beyond the first year of life 4.

Maternal Knowledge and Attitudes

• A survey of postpartum mothers found that the majority were aware that marijuana use while breastfeeding may be harmful to the infant, but a minority received counseling about the risks of marijuana use while breastfeeding 5.
• Mothers who were aware of the potential harmful effects of marijuana use during pregnancy were more likely to know that use while breastfeeding may be harmful to the infant 5.
• Those who received prenatal counseling about the risks of marijuana use while breastfeeding were more likely to know that marijuana or THC is found in breast milk 5.