What about marijuana use by women who are pregnant or breastfeeding?
As with alcohol and cigarettes, there likely is no “safe” amount of marijuana use during pregnancy. THC, the chemical in marijuana that makes a person “high,” can pass from mother to the unborn child through the placenta. This means the unborn child is exposed to THC used by the mother. Smoking also passes carbon monoxide to the unborn child, which disrupts the oxygen supply and can result in growth issues, possible premature birth, miscarriage or stillbirth. There is some evidence marijuana use during pregnancy can result in babies with low birth weight, certain birth defects and symptoms similar to fetal alcohol syndrome. THC can also be passed from the mother’s breast milk, potentially affecting the baby.