Since centuries, cannabis is used for recreational, spiritual and medicinal purposes. Today, cannabis is one of the most commonly used illicit substances, also among pregnant women. In the last decades, levels of Δ9-tetrahydrocannabinol in cannabis products have increased, and these higher levels contributed to our interest for investigating the effects of cannabis during pregnancy. The study described in this thesis was embedded within the Generation R Study, a prospective cohort study from foetal life onwards in a multiethnic urban population. In this study, we examined the associations of maternal cannabis use during pregnancy and several offspring outcomes. In order to determine whether cannabis use affects children because of intrauterine exposure, the possible influence of confounding factors should be considered. Moreover, the direct biological effect of intrauterine exposure was addressed by comparing the strength of the associations between maternal and paternal cannabis use during pregnancy and foetal growth using ultrasound measures. Additionally, to determine whether exposure to cannabis has an intrauterine influence or not, the timing of exposure was considered as well, i.e. the comparison between maternal cannabis use only before pregnancy and during pregnancy was made. This manuscript described the determinants of maternal cannabis use during pregnancy. Additionally, it discussed the agreement between maternal self-report of cannabis use during pregnancy and the presence of cannabis metabolites in urine. We addressed the association between maternal and paternal cannabis use and foetal growth and foetal redistribution observed using ultrasound measurements. Finally, this thesis focuses on the relation between parental cannabis use and child behavioural development and verbal and non-verbal cognitive development.

Generation R Study, cannabis exposure, pregnancy
W. van den Brink (Wim) , F.C. Verhulst (Frank) , A.C. Huizink (Anja)
Erasmus University Rotterdam
EMC Rotterdam (Generation R Study), J.E. Jurriaanse Stichting
Erasmus MC: University Medical Center Rotterdam

El Marroun, H. (2010, March 4). Prenatal Cannabis Exposure and Infant Development: “A Tolerated Matter”. Erasmus University Rotterdam. Retrieved from