Summary

Marijuana is consumed to a lesser extent than alcohol and tobacco. The age of greatest frequency of consumption coincides with the reproductive age. Cannabinoids have kinetic characteristics and mechanisms of action that pose a risk of fetal exposure and lactation. Pregnancy presents physiological changes that facilitate fetal exposure. The vulnerability of the endocannabinoid system at the stage of neurological development raises the suspicion of adverse effects associated with exposure to cannabis and derivatives. This work aims to update scientific information on the effects of cannabis and derivatives use during pregnancy and lactation. A descriptive review of articles published in peer-reviewed scientific journals between January 2010 and December 2018 was conducted. We included the analysis of databases using combinations of terms in English and Spanish: "marijuana", "cannabis", "cannabinoids", "pregnancy", "lactation". The effects associated with marijuana use in pregnancy are inconclusive, although there is growing evidence of its association with birth disorders, such as low birth weight and neurodevelopmental damage that impact the child and are maintained in late childhood and adolescence. No association was found with other indicators such as perinatal mortality and prematurity. Among the weaknesses of the studies reviewed, most are based on self-report and pose difficulties and uncertainties regarding the use of other substances as a confounder. So far the evidence is sufficient to adopt the precautionary principle and recommendation to avoid its consumption during pregnancy and lactation.