Understanding Hyperemesis Gravidarum
Unlike typical morning sickness that affects up to 80% of pregnant women, hyperemesis gravidarum is a severe condition characterized by persistent nausea and vomiting that can lead to more than 5% weight loss, dehydration, and electrolyte imbalances. The condition typically begins in the first trimester and may persist throughout pregnancy.
HG vs. Morning Sickness
Feature | Morning Sickness | Hyperemesis Gravidarum |
---|---|---|
Prevalence | 70-80% of pregnancies | 0.5-2% of pregnancies |
Duration | Usually subsides by 12-14 weeks | May persist throughout pregnancy |
Weight loss | Little to no weight loss | >5% pre-pregnancy weight |
Dehydration | Rare | Common and severe |
Hospitalization | Not required | Often necessary |
Symptoms and Signs
HG symptoms are severe and can significantly impact daily functioning and quality of life:
Primary Symptoms
- Severe, persistent nausea lasting all day
- Frequent vomiting (multiple times daily)
- Vomiting blood or bile (hematemesis)
- Inability to keep food or fluids down
- Weight loss of 5% or more of pre-pregnancy weight
Gastrointestinal Symptoms
- Sharp abdominal pain
- Burning abdominal pain
- Abdominal pain during pregnancy
- Diarrhea or constipation
- Excessive salivation (ptyalism)
- Food aversions and intolerance to smells
Systemic Symptoms
- Dizziness and lightheadedness
- Extreme weakness and fatigue
- Headaches
- Fainting or near-fainting episodes
- Rapid heart rate (tachycardia)
- Low blood pressure
Signs of Dehydration
- Dry mouth and decreased saliva
- Dark yellow urine or decreased urination
- Dry skin with poor elasticity
- Sunken eyes
- Low blood pressure
- Elevated heart rate
Complications and Warning Signs
- Severe pregnancy complications
- Electrolyte imbalances (low sodium, potassium)
- Ketosis from starvation
- Liver dysfunction
- Neurological symptoms (confusion, memory problems)
- Depression and anxiety
Causes and Risk Factors
The exact cause of hyperemesis gravidarum is not fully understood, but several factors are believed to contribute:
Hormonal Factors
- Human chorionic gonadotropin (hCG): Elevated levels correlate with HG severity
- Estrogen: High levels may contribute to nausea and vomiting
- Progesterone: May slow gastric emptying
- Thyroid hormones: Hyperthyroidism often accompanies HG
Genetic Factors
- Family history of HG increases risk
- Genetic variations in hormone receptors
- Inherited susceptibility to motion sickness
- Ethnic predisposition (higher in some populations)
Risk Factors
- Multiple pregnancy: Twins, triplets increase risk
- Previous HG: 15-80% recurrence rate
- Female fetus: Slightly higher risk
- First pregnancy: More common in primigravidas
- Young maternal age: Higher risk in younger women
- Molar pregnancy: Associated with very high hCG levels
Medical Conditions
- Thyroid disorders (hyperthyroidism)
- Gastrointestinal disorders
- Psychiatric conditions (depression, anxiety)
- Diabetes
- History of eating disorders
Diagnosis
HG diagnosis is primarily clinical, based on symptoms and exclusion of other conditions:
Diagnostic Criteria
- Persistent nausea and vomiting
- Weight loss >5% of pre-pregnancy weight
- Dehydration
- Electrolyte imbalances
- Ketonuria (ketones in urine)
- Inability to maintain nutrition and hydration
Laboratory Tests
- Electrolytes: Sodium, potassium, chloride levels
- Kidney function: Blood urea nitrogen, creatinine
- Liver function: ALT, AST, bilirubin
- Thyroid function: TSH, free T4
- Urinalysis: Specific gravity, ketones, protein
- Complete blood count: Check for hemoconcentration
Imaging and Other Tests
- Pelvic ultrasound to confirm pregnancy and rule out molar pregnancy
- Upper GI series if other conditions suspected
- Abdominal ultrasound if gallbladder disease suspected
Differential Diagnosis
- Gastroenteritis
- Food poisoning
- Peptic ulcer disease
- Gallbladder disease
- Pancreatitis
- Appendicitis
- Urinary tract infection
- Hyperthyroidism
Treatment and Management
Treatment goals include controlling nausea and vomiting, correcting dehydration and nutritional deficiencies, and preventing complications:
Initial Management
- IV fluid therapy: Normal saline or lactated Ringer's solution
- Electrolyte replacement: Potassium, magnesium, phosphorus
- Thiamine (Vitamin B1): To prevent Wernicke encephalopathy
- Nothing by mouth initially: Rest the GI tract
Anti-nausea Medications
- First-line:
- Pyridoxine (Vitamin B6) + Doxylamine
- Ondansetron (Zofran)
- Metoclopramide (Reglan)
- Second-line:
- Promethazine (Phenergan)
- Prochlorperazine (Compazine)
- Diphenhydramine (Benadryl)
- Third-line:
- Corticosteroids (methylprednisolone)
- Chlorpromazine
Nutritional Support
- Oral refeeding: Small, frequent, bland meals
- Enteral nutrition: Nasogastric or jejunostomy tube feeding
- Parenteral nutrition: Total parenteral nutrition (TPN) for severe cases
- Vitamin supplementation: Especially B vitamins and folate
Alternative Therapies
- Ginger: Natural anti-nausea properties
- Acupuncture/Acupressure: P6 (Nei Guan) point stimulation
- Aromatherapy: Peppermint or lemon scents
- Hypnosis: May help reduce symptoms
Hospitalization Criteria
- Severe dehydration
- Electrolyte imbalances
- Weight loss >5% of pre-pregnancy weight
- Ketonuria
- Inability to tolerate oral intake
- Failed outpatient management
Complications
Maternal Complications
- Nutritional deficiencies: Thiamine, folate, B12 deficiency
- Wernicke encephalopathy: Rare but serious neurological complication
- Mallory-Weiss tear: Esophageal tear from severe vomiting
- Pneumothorax: From forceful vomiting
- Dental problems: Enamel erosion from stomach acid
- Depression and anxiety: Psychological impact
- PTSD: Post-traumatic stress from severe illness
Fetal Complications
- Small for gestational age (SGA)
- Low birth weight
- Preterm birth
- Intrauterine growth restriction (IUGR)
Long-term Effects
- Fear of future pregnancies
- Impact on family planning decisions
- Chronic digestive issues
- Dental problems requiring ongoing care
Prognosis and Outlook
Typical Course
- Symptoms usually begin 4-6 weeks of pregnancy
- Peak severity around 9-13 weeks
- Most cases improve by 20 weeks
- Some women have symptoms throughout pregnancy
- Symptoms resolve after delivery
Factors Affecting Prognosis
- Early recognition and treatment
- Severity of initial presentation
- Response to medications
- Support system availability
- Previous pregnancy history
Future Pregnancies
- Recurrence rate: 15-80%
- May be less severe in subsequent pregnancies
- Preconception counseling recommended
- Early intervention strategies can be planned