What is the management for a pregnant woman at 37 weeks gestation with significant proteinuria (protein-creatinine ratio of 245) and 24-hour protein of 360?

Management of Proteinuria at 37 Weeks Gestation

This patient meets criteria for preeclampsia and should be delivered now, after maternal stabilization. 1, 2

Immediate Classification

This patient has preeclampsia based on:

• Protein-creatinine ratio of 245 mg/mmol (equivalent to approximately 2.4 g/day) - well above the diagnostic threshold of 30 mg/mmol 1
• 24-hour protein of 360 mg - above the 300 mg/day cutoff for significant proteinuria 1, 3
• Gestational age of 37 weeks - beyond 20 weeks when preeclampsia can be diagnosed 1

While the absolute proteinuria level is not massive (not nephrotic range), the presence of any significant proteinuria at term warrants delivery. 1, 2

Delivery Decision

Delivery should occur after maternal stabilization, regardless of whether severe features are present. The International Society for the Study of Hypertension in Pregnancy explicitly states that women with preeclampsia should be delivered if they have reached 37 weeks and zero days gestation. 1 This recommendation is echoed by ACOG guidance that delivery at 37 weeks is indicated for preeclampsia without severe features. 2

Critical point: Do not delay delivery based on the degree of proteinuria alone - proteinuria severity does not independently predict adverse outcomes and should not be used as the sole criterion for timing delivery. 3, 4 The gestational age of 37 weeks is the primary driver of the delivery decision. 1, 2

Pre-Delivery Maternal Assessment and Stabilization

Blood Pressure Management

• Measure current blood pressure immediately - if ≥140/90 mmHg, initiate antihypertensive therapy targeting diastolic BP of 85 mmHg and systolic BP 110-140 mmHg 1, 2
• For non-severe hypertension (140-159/90-109 mmHg): Use oral methyldopa, labetalol, or nifedipine 1, 2
• For severe hypertension (≥160/110 mmHg): Initiate urgent treatment with oral nifedipine or IV labetalol/hydralazine in a monitored setting 1, 2
• Avoid reducing diastolic BP below 80 mmHg as this may compromise placental perfusion 1

Magnesium Sulfate Decision

Administer magnesium sulfate for seizure prophylaxis if ANY of the following are present: 1, 2

• Severe hypertension (≥160/110 mmHg) with proteinuria
• Neurological signs or symptoms (severe headache, visual changes, hyperreflexia with clonus)
• Any other severe features

Dosing: 4-5g IV loading dose over 5 minutes, followed by 1-2g/hour continuous infusion 2

Laboratory Assessment

Obtain the following tests to assess for progression to severe features: 1, 2

• Complete blood count - focusing on hemoglobin and platelet count (thrombocytopenia <100,000 suggests HELLP syndrome) 1
• Comprehensive metabolic panel - including AST/ALT (elevated >2x normal suggests liver involvement), creatinine (>1.1 mg/dL or doubling suggests renal insufficiency), and uric acid 1, 2

These labs should be obtained at minimum twice weekly, or more frequently if clinical deterioration occurs. 1

Clinical Assessment

• Assess for clonus and deep tendon reflexes - hyperreflexia with clonus indicates neurological involvement requiring magnesium 1
• Evaluate for symptoms: severe persistent headache, visual scotomata, right upper quadrant or epigastric pain, nausea/vomiting 1
• Monitor for pulmonary edema - dyspnea, oxygen desaturation 1

Fetal Assessment

Initial Evaluation

• Perform biophysical profile including ultrasound assessment of fetal biometry, amniotic fluid volume, fetal breathing movements, body movements, and tone 2
• Continuous electronic fetal monitoring to assess for decelerations or non-reassuring patterns 2

Important caveat: Do not delay delivery based solely on non-reactive fetal testing - at 37 weeks with preeclampsia, delivery is indicated regardless of fetal testing results. 2

Delivery Planning

• Vaginal delivery is preferred unless cesarean is indicated for standard obstetric reasons 1, 2
• Induction of labor is appropriate and should be initiated after maternal stabilization if severe features are present 2
• Timing: Delivery should occur within 24-48 hours of diagnosis once maternal stabilization is achieved 1, 2

Monitoring for Severe Features Requiring Expedited Delivery

Even if severe features are not initially present, expedite delivery immediately if any of the following develop: 1

• Repeated episodes of severe hypertension despite treatment with 3 antihypertensive classes
• Progressive thrombocytopenia (platelets declining toward <100,000)
• Progressively abnormal liver enzymes (AST/ALT rising >2x normal)
• Worsening renal function (creatinine >1.1 mg/dL or doubling)
• Pulmonary edema
• Severe intractable headache, repeated visual scotomata, or seizures
• Non-reassuring fetal status

Common Pitfalls to Avoid

Do not repeat proteinuria measurements - the amount of proteinuria does not correlate with adverse outcomes and monitoring it may lead to unnecessary preterm deliveries. 3, 4 The diagnosis is already established.

Do not underestimate disease severity based on the "mild" classification - all preeclampsia can rapidly progress to eclampsia or HELLP syndrome. 2 While higher proteinuria levels (>900 mg/mmol or approximately 9 g/day) are associated with increased risk of adverse outcomes 5, this patient's moderate proteinuria at 37 weeks still mandates delivery. 1

Do not delay delivery to achieve "better" fetal lung maturity - at 37 weeks, the fetus is term and the risks of continuing pregnancy with preeclampsia outweigh any marginal benefit from additional days in utero. 1, 2

Postpartum Considerations

• Continue close monitoring for 48-72 hours postpartum - 20% of HELLP syndrome cases occur within 48 hours of delivery 1
• Reassess proteinuria at 3 months postpartum - it should resolve; persistent proteinuria suggests underlying chronic kidney disease 3
• Most women with preeclampsia-related proteinuria recover completely - even those with heavy proteinuria (>5 g/day) typically have no residual renal dysfunction 6