Hyperemesis Gravidarum

Symptoms

• Severe, persistent nausea
• Frequent vomiting, often more than 3-4 times a day
• Inability to keep down food or fluids
• Significant weight loss (more than 5% of your weight before pregnancy)
• Extreme tiredness and lack of energy (fatigue and lethargy)
• Excessive salivation (ptyalism)
• A heightened sense of smell (hyperolfaction)
• Strong dislikes for certain foods
• Dizziness or lightheadedness
• Emergency Signs (Seek immediate medical help if you experience):
• Inability to keep any liquids down for more than 12 hours
• Very dark urine or no urination
• Severe dizziness or fainting
• A rapid heart rate
• Confusion, severe headache, changes in vision, numbness, or difficulty walking (these could be signs of Wernicke's encephalopathy)
• Severe pain in your abdomen or chest
• Vomiting blood
• Fever

Causes & Risk Factors

• The exact cause of Hyperemesis Gravidarum (HG) is not fully understood and is believed to be multifactorial. It is not a psychological condition, although psychological distress can be a significant consequence.
• Rapidly rising levels of human chorionic gonadotropin (hCG), a hormone produced during pregnancy, are strongly implicated. This is supported by the timing of peak hCG levels coinciding with peak HG symptoms, and the higher incidence of HG in conditions with higher hCG levels, such as multiple gestation (e.g., twins) or molar pregnancy.
• There is a clear genetic component, meaning you are at a significantly increased risk if your mother or sister had HG.
• Recent research has identified a strong link between HG and the hormone Growth Differentiation Factor 15 (GDF15), which is produced by the placenta. GDF15 acts on a specific receptor in the brainstem (GFRAL) to induce nausea and vomiting. Women with HG may have higher levels of GDF15 or increased sensitivity to it.
• Previous pregnancy with Hyperemesis Gravidarum (this is the highest risk factor)
• Multiple gestation (e.g., carrying twins or triplets)
• Hydatidiform mole (a type of abnormal pregnancy)
• A family history of HG (if your mother or sister had it)
• A history of motion sickness or migraines
• Carrying a female fetus
• Younger maternal age
• Nulliparity (this is your first pregnancy)
• Pre-existing psychiatric illness (though this may sometimes be a consequence rather than a cause)
• Certain gastrointestinal disorders, such as Helicobacter pylori infection
• Higher Body Mass Index (BMI)

Diagnosis

• Hyperemesis Gravidarum (HG) is a diagnosis of exclusion, meaning other causes of severe vomiting must be ruled out. The typical criteria include:
• Persistent vomiting that is not related to other medical conditions.
• Evidence of acute starvation, usually indicated by ketones in your urine (ketonuria).
• Significant weight loss, most commonly defined as more than 5% of your pre-pregnancy body weight.
• Your doctor will ask about the onset, duration, and frequency of your nausea and vomiting, your ability to tolerate food and fluids, and any weight loss. They will also ask about other symptoms to rule out different causes of vomiting.
• A physical examination will assess your hydration status (e.g., skin turgor, mucous membranes, changes in blood pressure or heart rate when standing), measure your current weight to calculate weight loss, and examine your abdomen to rule out other problems.
• Urine tests will check for ketones and specific gravity (a measure of urine concentration, indicating dehydration).
• Blood tests will include a comprehensive metabolic panel to check electrolytes (which can show imbalances like low sodium or potassium), kidney function (creatinine and BUN), and liver enzymes (which can be elevated in up to 50% of HG patients). Thyroid function tests may also be done to check for gestational transient thyrotoxicosis.
• A pelvic ultrasound is recommended to confirm a viable pregnancy and to rule out conditions like multiple gestation or hydatidiform mole, which are risk factors for HG.
• Your doctor will consider other conditions that can cause similar symptoms, such as gastroenteritis, kidney infection (pyelonephritis), hepatitis, pancreatitis, gallbladder inflammation (cholecystitis), peptic ulcer disease, diabetic ketoacidosis, or certain neurological conditions.

Treatment Options

• Treatment for Hyperemesis Gravidarum (HG) typically follows a stepwise approach, starting with conservative measures and escalating to medications and hospitalization if needed.
• Lifestyle and Non-Pharmacological Approaches:
• Eat small, frequent meals throughout the day.
• Choose bland, dry, and high-protein foods.
• Avoid spicy or fatty foods and other known triggers that worsen your nausea.
• Acupressure at the P6 (Neiguan) point on the wrist may offer some relief.
• Ginger has some evidence for mild nausea and vomiting of pregnancy but may not be sufficient for severe HG.
• Medical Treatment (Pharmacotherapy):
• First-line: Vitamin B6 (pyridoxine) alone or in combination with Doxylamine.
• Second-line (if first-line treatment is not enough): Antihistamines (such as Diphenhydramine, Meclizine, or Cyclizine) or Dopamine antagonists (such as Metoclopramide or Prochlorperazine).
• Third-line (for persistent, severe symptoms): Serotonin 5-HT3 receptor antagonists, such as Ondansetron. While some studies have suggested a small, uncertain increased risk of oral clefts with first-trimester use, the absolute risk is low, and other studies have not confirmed this. Your doctor will discuss the benefits and risks, including a risk of maternal QT interval prolongation.
• Fourth-line / Adjunctive (for very severe, resistant cases): Corticosteroids (such as Methylprednisolone or Prednisolone). These are generally reserved for severe cases and should typically be avoided before 10 weeks of gestation due to a small associated risk of fetal oral clefting.
• Emergency Treatment and Hospitalization:
• Hospitalization may be necessary if you cannot tolerate liquids, continue to lose weight despite outpatient therapy, or have significant electrolyte imbalances or ketonuria.
• Intravenous (IV) fluids will be given to correct dehydration, typically with normal saline. Electrolytes, especially potassium, will be replaced as needed.
• Thiamine (Vitamin B1) is a crucial intervention. IV thiamine must be administered before any dextrose-containing fluids are given to prevent a serious neurological condition called Wernicke's encephalopathy.
• For prolonged inability to eat, nutritional support may be provided. Enteral nutrition (feeding through a tube placed into the stomach or small intestine) is generally preferred over parenteral nutrition (IV feeding) due to a lower risk of complications.

Frequently Asked Questions