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Study breakdown

Cannabis for Severe Morning Sickness? It Might Actually Be Making Things Worse

evidence
The takeaway

Cannabis use during pregnancy for severe nausea may represent unrecognized cannabinoid hyperemesis syndrome (CHS), which would mean cannabis is causing the very symptoms women are trying to treat.

Read this if you are pregnant with severe nausea and using cannabis, or if you are an obstetrician managing hyperemesis gravidarum.

Up to 3%

Proportion of pregnancies affected by severe nausea/vomiting, some of which may be cannabis-caused CHS

What the researchers found

The review highlights that severe nausea and vomiting of pregnancy (affecting up to 3% of pregnancies) is increasingly associated with cannabis use, as pregnant individuals believe cannabis is a natural, safe antiemetic. However, some of these cases may actually be cannabinoid hyperemesis syndrome (CHS), where chronic cannabis use itself causes the severe vomiting. CHS may be more common in pregnancy than previously recognized. The diagnostic confusion is compounded by variable legal status, personal acceptance, and challenging patient-provider communication.

Why it matters

If a significant proportion of severe pregnancy nausea attributed to hyperemesis gravidarum is actually CHS, then continued cannabis use is making these patients worse, not better. Differential diagnosis is critical for proper treatment.

The numbers in context

- Severe NVP/HG affects up to 3% of pregnancies

- Cannabis discouraged by Surgeon General and ACOG

- CHS may be more common than previously thought

- Variable legal status across states complicates discussion

How the study worked

Clinical review and commentary on the intersection of cannabis use, severe nausea of pregnancy, and cannabinoid hyperemesis syndrome.

Who was studied

Pregnant individuals with severe nausea and vomiting who use cannabis

What this study cannot tell us

Not a systematic review or original research. The overlap between HG and CHS is difficult to quantify with current diagnostic tools. Provider-patient communication barriers may limit data quality.

How to read the evidence

Clinical review and commentary. Raises an important diagnostic concern but lacks quantitative data on the CHS-HG overlap.

When this study was published

Published in 2023. Addresses an increasingly recognized clinical problem.

The bigger picture

The CHS-pregnancy overlap represents one of the most clinically important diagnostic challenges in prenatal cannabis medicine. Getting this diagnosis wrong means treating with the very substance causing harm.

Questions still open

  • What proportion of hyperemesis gravidarum cases involve cannabis use?
  • Could a trial of cannabis cessation reliably distinguish HG from CHS in pregnancy?
  • Are there biomarkers that could differentiate HG from CHS?

Read the original research

Addressing cannabis consumption among patients with hyperemesis gravidarum.

AJOG global reports, 3(2), 100180

Citation

Galvin, Shelley L; Coulson, Carol C. (2023). Addressing cannabis consumption among patients with hyperemesis gravidarum.. AJOG global reports, 3(2), 100180. https://doi.org/10.1016/j.xagr.2023.100180