EFFECT OF PRENATAL MARIJUANA EXPOSURE ON THE COGNITIVE-DEVELOPMENT OFOFFSPRING AT AGE-3

Marijuana is the most commonly used illicit substance among pregnant w omen. Although there has been substantial concern about the effects of substance use during pregnancy, few studies have assessed the effects of prenatal exposure to marijuana and even fewer have provided longit udinal data on the developmental outcome of offspring. This is a repor t from a longitudinal study of substance use during pregnancy. The wom en in the cohort were of lower socioeconomic status, most were single, half were white and half were African-American. Women were interviewe d at the fourth and seventh prenatal months, and women and children we re assessed at delivery, 8, 18, and 36 months. Pediatric assessment in cluded physical and cognitive development. At each study phase, mother s were interviewed about life style, living situation, current substan ce use, sociodemographic, and psychological status. Findings are repor ted on 655 women and children who were assessed at the third year. The re were significant negative effects of prenatal marijuana exposure on the performance of 3-year-old children on the Stanford-Binet Intellig ence Scale. The effects were associated with exposure during the first and second trimesters of pregnancy. Among the offspring of white wome n, these effects were moderated by the child's attendance at preschool /day-care at age three.