Description

• Hyperemesis gravidarum is intractable vomiting in a pregnant woman that interferes with fluid and electrolyte balance as well as nutrition:
  • Usually associated with the first 8 to 20 weeks of pregnancy
  • Believed to have biomedical and behavioral aspects
  • Associated with high estrogen and human chorionic gonadotropin (hCG) levels
  • Symptoms usually begin ~2 weeks after first missed period and normally resolves by the 20th week
• System(s) affected: endocrine/metabolic; gastrointestinal; reproductive
• Synonym(s): morning sickness

Pregnancy Considerations
While morning sickiness is common during pregnancy, hyperemesis gravidarum is a rare condition.

Epidemiology

Incidence
Hyperemesis gravidarum occurs in 1–2% of pregnancies.

Prevalence
Hyperemesis gravidarum is the most common cause of hospitalization in the first half of pregnancy and the second most common cause of hospitalization of all pregnant women.

Etiology and Pathophysiology

Etiology unknown. Proposed influences include:

• Hyperthyroidism
• Hyperparathyroidism
• Pregnancy hormones
• Liver dysfunction
• Autonomic nervous system dysfunction
• Central nervous system (CNS) neoplasm
• Addison disease
• Possible psychological factors

Genetics
Increased risk if maternal family history of hyperemesis gravidarum

Risk Factors

• Nulliparity
• Multiple gestations
• History of migraines
• History of motion sickness
• Black or Asian women
• Gestational trophoblastic disease
• Fetus with trisomy 21
• Female fetus
• Possible association with Helicobacter pylori infection

General Prevention

Anticipatory guidance regarding dietary habits to avoid dehydration and nutritional depletion

• Small, frequent meals
• Avoiding an overly empty or full stomach

Pregnancy Considerations

• 2% of pregnancies have electrolyte disturbances.
• 50% of pregnancies have at least some gastrointestinal disturbance.

Commonly Associated Conditions

Hyperthyroidism