Cannabis Hyperemesis Syndrome: An Underrecognized Cause of Nausea and Vomiting in Pregnancy

Introduction: Cannabis Hyperemesis Syndrome (CHS) is characterized by refractory and recurrent nausea and vomiting in birthing people with chronic cannabis use and is emerging as an increasingly common diagnosis in patients who present to the emergency department. The objective of this retrospective case series was to describe presentation, management and outcomes of CHS during pregnancy. Methods: Patients were identified by the investigator at two tertiary care centers in Kansas City from January 2019 to October 2021. Patients were included if (1) intrauterine pregnancy (2) refractory and recurrent nausea and vomiting without acute cause, and (3) documented chronic cannabis use which preceded symptom onset were noted. The study was approved by the UMKC IRB (#308059). Results: Twelve patients were identified who met inclusion criteria, ranging in age from 17 to 32 years (mean 23.2 ± 4.5). Eleven patients reported daily cannabis use. The mean number of emergency department visits during pregnancy for nausea and vomiting was 8.9 (± 7.1). Patients presented at a wide range of gestational ages, between 4 and 37 weeks (mean 19.6 ± 9.8). Compulsive hot water bathing for symptom relief was documented in 33% of cases (4 of 12). The rate of fetal growth restriction in this series was 44% (4 of 9). Despite counseling, only one patient successfully discontinued cannabis use. Conclusions: CHS should be considered in the differential diagnosis of nausea and vomiting in pregnancy. Patients who meet criteria should be counseled about cannabis cessation as part of treatment recommendations.