Cannabis use during pregnancy and its effect on the fetus, newborn and later childhood: A systematic review

INTRODUCTION: Cannabis and its derivatives are becoming increasingly popular in women’s preferences during pregnancy in order to relieve nausea. The present study examines cannabis use during pregnancy and its effects on the fetus, newborn and later childhood. METHODS: All primary studies were searched in the databases: PubMed, Scopus, Medline during the period June 2019 to August 2020. The keywords used were ‘pregnancy’, ‘pregnant women’, ‘cannabis’, ‘marijuana’, ‘fetus’, ‘newborn’, ‘childhood’, and combined with ‘AND’ and ‘OR’ Boolean operators. Inclusion criteria were: pregnant users of cannabis as the study group and pregnant non-users of cannabis as the control group; the articles could be in English or in Greek. The exclusion criteria were: unpublished studies, reviews, presentations at conferences, and animal studies. RESULTS: From the systematic review of the literature, the study included 13 primary research studies in which it was found that the children of mother-user faced: disorders in the sleep cycle, memory problems, hyperactivity, increased chances of low birth weight, prematurity with lower Apgar score in the 1st and 5th minutes and hospitalization in an NICU, DNA methylation at the position CpG.32, and modifications in the brain, especially in the amygdala. In addition, girls had more aggressive behavior at the age of 18 months, shorter breastfeeding period, and neonatal death. CONCLUSIONS: The use of cannabis during the gestation period by the mother, aggravates the physical and mental development of the fetus, the newborn and the later childhood.