What are the signs and symptoms of preeclampsia?

Signs and Symptoms of Preeclampsia

Preeclampsia presents with new-onset hypertension (≥140/90 mmHg) after 20 weeks of gestation, classically accompanied by proteinuria (≥300 mg/24h or ≥+ on dipstick), though proteinuria is no longer required for diagnosis if other severe features are present 1, 2.

Core Diagnostic Signs

Hypertension

• Systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg developing after 20 weeks gestation in a previously normotensive woman 3
• Severe hypertension defined as systolic ≥160 mmHg or diastolic ≥110 mmHg 2
• Note: Eclampsia can occur even without severe hypertension—34% of eclamptic women had maximum diastolic BP ≤100 mmHg 3

Proteinuria

• ≥300 mg protein in 24-hour urine collection (most reliable quantification method) 3
• ≥+ on urine dipstick (screening tool)
• Protein-creatinine ratio ≥30 mg/mmol on random sample for screening 3
• Important caveat: Proteinuria is no longer mandatory for diagnosis if other severe features are present 2

Maternal Symptoms (Severe Features)

These symptoms indicate potential end-organ dysfunction and warrant urgent evaluation:

Neurological

• Persistent headache (often severe, unrelieved by acetaminophen) 3
• Visual disturbances (blurred vision, scotomata, photophobia) 3, 2
• Seizures (defining feature of eclampsia) 4

Gastrointestinal/Hepatic

• Epigastric pain or right upper quadrant pain (suggests hepatic capsule distension or HELLP syndrome) 3, 2
• Nausea/vomiting 5

Other Physical Signs

• Edema (present in 53% of preeclamptic women before diagnosis, though not diagnostic alone as it occurs in 18% of normal pregnancies) 6
• Excessive weight gain (>0.85 kg/week in third trimester carries 11.6-fold increased risk) 6
• Rapid BMI increase (>0.39-0.41 kg/m²/week has 84% sensitivity and 81-91% specificity for predicting severe preeclampsia) 6

Laboratory and Organ Dysfunction Markers

Hematologic

• Thrombocytopenia (<100,000/μL, severity criterion) 2
• Hemolysis (component of HELLP syndrome) 2

Hepatic

• Elevated liver transaminases (>2× normal values) 2
• Hypoalbuminemia (plasma albumin <32.6 g/L) 6

Renal

• Renal impairment/failure 2
• Serum creatinine elevation 2

Pulmonary

• Acute pulmonary edema 2

Fetal Signs

• Reduced fetal movements 3
• Small for gestational age infant (fetal growth restriction) 3

Clinical Algorithm for Assessment

After 20 weeks gestation, assess for ANY of the following 3:

1. New hypertension alone → Check for proteinuria and symptoms
2. New proteinuria alone → Measure blood pressure and assess for symptoms
3. Maternal symptoms alone (headache, visual changes, epigastric pain) → Measure BP and check proteinuria
4. Fetal signs (reduced movements, growth restriction) → Full preeclampsia assessment

Critical point: Any single sign or symptom may be the first indication of preeclampsia 3. The condition can progress from diagnosis to life-threatening complications in an average of 2 weeks, with 25-55% of severe cases requiring delivery within 48 hours of admission 3.

Common Pitfalls

• Do not dismiss symptoms in the absence of severe hypertension—eclampsia occurs in one-third of cases without BP >100 mmHg diastolic 3
• Edema alone is not diagnostic—it lacks predictive value and occurs commonly in normal pregnancy 3
• Weight change does not reliably precede other signs, though excessive gain (>0.85 kg/week) is a significant risk factor 3, 6
• Traditional signs and symptoms have poor selectivity—29.2% of pregnancies have ≥1 documented sign/symptom, but only 14.2% receive a preeclampsia diagnosis 5