BACKGROUND: Increased use of marijuana in pregnancy (3.9% in 2014 compared with 2.4% in 2002 in a recent self-reported survey) is a significant problem and poses potential health risks for the developing fetus. Studies have shown that the fetal endocannabinoid receptor system may be vulnerable to intrauterine exposure to THC (Tetrahydrocannabinol) and may produce long-term consequences on behavior and psychopathology in children. There are, however, limited studies evaluating the impact of prenatal marijuana use on neurodevelopmental outcomes in children. DESIGN/METHODS: Case-control study; Cases were patients with intrauterine exposure to marijuana confirmed by positive maternal urine testing for THC during any trimester of pregnancy. Controls were patients without intrauterine THC exposure matched by age, sex and race. Both groups were born and received primary care services at a university affiliated community hospital. Chart review was performed to assess attainment of developmental milestones during well-child visits at 6, 9, 12, 15, 18 and 24 months of age. The objective of the study was to examine the impact of intrauterine marijuana exposure on neurodevelopment during the first 24 months of life. RESULTS: 326 charts were reviewed, 109 cases and 217 controls. Bivariate analysis showed that ethnicity, exclusive breastfeeding, prenatal marijuana exposure and trimester of exposure were significantly correlated with delayed developmental milestones. Logistic regression showed that prenatal marijuana exposure was significantly associated with developmental delay at 15 (OR=2.682, 95% CI: 1.063 - 6.769) and 18 months of age (OR=2.454, 95% CI: 1.059 - 5.688). The study showed that the affected development domains in children with prenatal THC exposure were Fine motor ( OR= 2.32, 95% CI: 0.99 - 5.44) and Social ( OR=6.88, 95% CI: 3.08 - 15.35). No significant risk of delay in gross motor and language areas were identified. Smoking marijuana during the 2nd trimester represented a significant risk of delay at 18 months (OR=3.891, 95% CI: 1.796 - 8.428). CONCLUSION(S): Prenatal marijuana exposure was associated with developmental delay at 15 and 18 months of age. Physicians and parents should be aware of the potential impact of marijuana on post-natal neurodevelopmental milestones. Future studies should examine this relationship using a prospective study design.

RISK OF ANY DEVELOPMENTAL DELAY AND THC EXPOSURE AT SPECIFIC AGES

RISK OF ANY DEVELOPMENTAL DELAY AND THC EXPOSURE AT SPECIFIC AGES

RELATIONSHIP BETWEEN EXPOSURE TO THC AND AFFECTED DEVELOPMENTAL DOMAINS

RELATIONSHIP BETWEEN EXPOSURE TO THC AND AFFECTED DEVELOPMENTAL DOMAINS