The condition termed cannabinoid hyperemesis syndrome (CHS) was characterized a decade ago by Allen et al. and includes cyclic episodes of nausea and vomiting and the learned behavior of hot bathing in individuals with chronic cannabis abuse. During pregnancy, the differential diagnosis of this syndrome is challenging since it can be masked by typical symptoms of early pregnancy or by hyperemesis gravidarum, a complication of early pregnancy associated with excessive nausea and vomiting. We herein describe the case of a 21-year-old primigravida patient diagnosed with hyperemesis gravidarum at 6 weeks of gestation and with pre-eclampsia at 35 weeks. At 30 weeks of gestation, a drug screen was performed that was positive for cannabis; therefore, a diagnosis of CHS was made. After labor induction, the patient delivered an infant who developed normally and had a negative drug test of the umbilical cord blood. Esophagogastroduodenoscopy was performed 9 days post-delivery, with biopsies taken of the duodenal, gastric, and esophageal tissues. Moderate chronic gastritis with lymphoid aggregates and slight acute inflammation were noticed, whereas no malignancy, dysplasia, or goblet cell metaplasia was detected. A number of helicobacter-like organisms were identified by H. pylori immunostaining. Presented here is the first case reporting an association of chronic cannabis use with H. pylori colonization and pre-eclampsia in pregnancy, which brings to light the possible involvement of a cannabinoid-related pathway in the link between pregnancy-specific complications and bacterial colonization.