Hyperemesis Gravidarum
Hyperemesis gravidarum (HG) is a severe form of pregnancy nausea and vomiting causing significant dehydration, weight loss, and malnutrition. It affects 0.3–3% of pregnancies and often requires medical treatment.
Common Causes
- Extreme sensitivity to hCG hormone — associated with high hCG levels (twins, molar pregnancy increase risk)
- Genetic component — runs in families
- Thyroid hormone fluctuations linked to high hCG levels
- Helicobacter pylori infection possibly linked to HG severity
- Psychological factors may influence severity but do not cause HG
Remedies That May Help
IV Fluids and Electrolytes
The primary treatment for dehydration — typically administered in hospital or infusion clinic.
Anti-Nausea Medications
Ondansetron (Zofran), promethazine, metoclopramide, and doxylamine/B6 (Diclegis) are prescribed based on severity and individual response.
Thiamine (Vitamin B1) Supplementation
Essential to prevent Wernicke encephalopathy from prolonged vomiting — almost always prescribed in hospitalized HG patients.
Nutritional Support
Enteral nutrition (via nasogastric tube) or parenteral nutrition (IV) may be needed in severe cases where no oral intake is tolerated.
Rest and Stress Reduction
A supportive home environment and reduced demands are important for recovery.
When to Call Your Doctor
- Vomiting more than 3–4 times per day with inability to keep fluids down
- Signs of dehydration: dark urine, dizziness, confusion, dry mouth, not urinating
- Weight loss of more than 5% of pre-pregnancy body weight
- Vomiting blood or coffee-ground material
- Severe weakness, confusion, or inability to function
Frequently Asked Questions
How is hyperemesis gravidarum different from morning sickness?
Morning sickness involves nausea and some vomiting but allows adequate hydration and nutrition. HG is defined by persistent severe vomiting causing dehydration, weight loss (>5%), electrolyte imbalance, and inability to function.
Will my baby be affected by hyperemesis gravidarum?
With proper treatment, most babies born to mothers with HG do well. Severe untreated HG with significant malnutrition can affect birth weight.
When does hyperemesis gravidarum end?
For many women, HG improves by weeks 14–20. However, some women experience symptoms throughout their entire pregnancy.
Is Zofran (ondansetron) safe in pregnancy?
Ondansetron is widely used for HG. Current evidence does not confirm increased risk of birth defects, though some earlier studies raised concerns. The decision balances the risks of HG (dehydration, malnutrition) against any potential medication risk.
Will HG come back in future pregnancies?
Yes — recurrence in subsequent pregnancies is common, occurring in 15–81% of cases. Preventive treatment starting early in the next pregnancy may reduce severity.