3. Marijuana

Marijuana is the most commonly used illicit substance in the United States, and it is the most common recreational drug used during pregnancy.

It is important to know that the psychoactive ingredient in marijuana, 1,9-tetrahydrocannabinol (THC), is a substance which accumulates in fat. THC is eventually broken down by the liver before being excreted, but it may stay in fat tissue for days. Thus, the effects of using marijuana may persist for some time. Marijuana has multiple effects on the mother including producing tachycardia (a fast heart rate), exercise intolerance, bronchitis (inflammation of the airways in the lungs), sinusitis (inflammation of the sinuses), and pharyngitis (inflammation of the back of the mouth and throat). The effects of marijuana on the fetus are the subject of some debate. There are reports in the literature of decreased body length, intrauterine growth retardation, neurobehavioral effects, and an increased incidence of prematurity. These findings, however, have not been consistent in all studies so there are no firm conclusions about the effects of marijuana on a fetus.

(The material presented here has been adopted from a pamphlet written

and distributed by the American College of Obstetricians and Gynecologists.)