Hyperemesis gravidarum is severe nausea and vomiting in pregnancy that leads to dehydration, loss of more than 5 percent of body weight or electrolyte problems. It usually starts before week 9, is more common with twins or molar pregnancy, and often eases by week 20.
Key symptoms
- Persistent vomiting, often many times a day
- Unable to keep food or fluids down
- Weight loss and weakness
- Dizziness, thirst and dark, scant urine
- Excess saliva and strong aversion to smells
What you find on exam
- Signs of dehydration: dry mouth, fast pulse, low pressure on standing
- Weight compared with before pregnancy
- Soft abdomen without focal tenderness
- Fetal heart tones when the pregnancy is far enough along
Tests
- Urine ketones and specific gravity
- Electrolytes (low potassium), kidney function, glucose
- Liver tests and TSH; both can be mildly abnormal
- Pelvic ultrasound to look for twins or molar pregnancy
Treatment basics
- IV fluids and electrolyte replacement
- Thiamine before any dextrose to prevent Wernicke encephalopathy
- Doxylamine with pyridoxine as first-line medicine
- Ondansetron or metoclopramide if symptoms continue
- Small, frequent bland meals; tube feeding for rare refractory cases
Red flags
- Confusion, double vision or unsteady walking (Wernicke encephalopathy)
- Abdominal pain, fever or headache, which point to another cause
- Low potassium, kidney injury, or still unable to keep fluids down after treatment
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.