Management of Preeclampsia
All women with preeclampsia should be assessed in hospital at initial diagnosis, with blood pressure treated when ≥140/90 mm Hg targeting diastolic BP of 85 mm Hg, and delivery is the definitive treatment at ≥37 weeks or earlier if severe features develop. 1
Initial Assessment and Hospitalization
When preeclampsia is first diagnosed, immediate hospital assessment is mandatory 1. After initial stabilization and if the condition is stable, selected patients may transition to outpatient management with reliable BP monitoring and symptom reporting 1. However, this requires careful patient selection and close surveillance.
Blood Pressure Management
Treatment Thresholds and Targets
For non-severe hypertension (140-159/90-109 mm Hg):
- Initiate antihypertensive therapy at BP ≥140/90 mm Hg 1
- Target diastolic BP of 85 mm Hg (systolic 110-140 mm Hg) 1
- Reduce or stop medications if diastolic BP falls <80 mm Hg 1
First-line oral agents include:
- Methyldopa
- Labetalol
- Nifedipine
- Oxprenolol
Second/third-line agents: hydralazine, prazosin 1
Severe Hypertension (≥160/110 mm Hg)
This requires urgent treatment in a monitored setting 1. The 2025 Circulation guidelines emphasize this is a medical emergency requiring immediate intervention 2.
Acceptable agents for acute treatment:
- Oral nifedipine (preferred)
- IV labetalol
- IV hydralazine
- Oral labetalol if IV unavailable 1
Magnesium Sulfate for Seizure Prophylaxis
Administer magnesium sulfate to women with:
- Preeclampsia with proteinuria AND severe hypertension, OR
- Hypertension with neurological signs/symptoms 1
Standard dosing regimen:
- Loading dose: 4 g IV or 10 g IM
- Maintenance: 5 g IM every 4 hours OR 1 g/hour IV infusion
- Continue until delivery and for at least 24 hours postpartum 1
The 2025 guidelines confirm magnesium sulfate remains essential for eclampsia prophylaxis in severe preeclampsia 2.
Maternal Monitoring Protocol
Clinical assessments must include:
- BP monitoring (frequency based on severity)
- Repeated proteinuria assessment if not initially present
- Neurological examination including clonus assessment 1
Laboratory testing at minimum twice weekly:
- Complete blood count (hemoglobin, platelet count)
- Liver transaminases (AST, ALT)
- Serum creatinine
- Uric acid 1
Critical pitfall: Test more frequently if clinical status changes. All preeclampsia can rapidly progress to severe disease—there should be no attempt to classify as "mild" versus "severe" clinically 1.
Fetal Monitoring
Initial assessment:
- Confirm fetal well-being with ultrasound
- Assess fetal biometry, amniotic fluid volume, and umbilical artery Doppler 1
Ongoing surveillance:
- Every 2 weeks if initial assessment normal
- More frequent monitoring if fetal growth restriction present 1
Timing of Delivery
Delivery is Mandatory at ≥37 Weeks
Deliver all women with preeclampsia at 37 weeks and 0 days gestation 1. This is the definitive treatment 2.
Indications for Immediate Delivery (Regardless of Gestational Age)
Deliver immediately if ANY of the following develop:
- Repeated severe hypertension despite 3 classes of antihypertensives
- Progressive thrombocytopenia
- Progressively abnormal liver or renal function tests
- Pulmonary edema
- Severe intractable headache, repeated visual scotomata, or convulsions
- Non-reassuring fetal status 1
Important caveat: Neither uric acid level nor degree of proteinuria should be used as delivery indications 1.
Management Before 37 Weeks
34-37 weeks: Expectant conservative management is acceptable if stable, with close monitoring 1
<34 weeks: Conservative management at a center with Maternal-Fetal Medicine expertise, but deliver immediately if severe features develop 1
<24 weeks (limits of viability): Counsel that pregnancy termination may be required 1
Corticosteroids
Administer antenatal corticosteroids for fetal lung maturation between 24+0 and 34+0 weeks gestation when preterm delivery is anticipated 1. Do not delay delivery to complete steroid courses if maternal or fetal indications for immediate delivery exist.
Postpartum Management
The 2025 Circulation guidelines highlight that postpartum hypertension management is critical, as hypertensive disorders can worsen or initially present after delivery and account for up to 44% of pregnancy-related deaths in the first 6 days postpartum 2.
Treatment threshold postpartum: SBP ≥150 mm Hg or DBP ≥100 mm Hg 2
Many clinicians also treat stage 2 hypertension (>140/90 mm Hg) targeting <130/80 mm Hg postpartum, consistent with non-pregnant guidelines 2.
Key Clinical Pitfalls
- Never assume "mild" preeclampsia is benign—all cases can rapidly deteriorate 1
- Do not use plasma volume expansion routinely in preeclampsia 1
- Monitor closely in early postpartum period—significant maternal morbidity and mortality occur in the first week after delivery 2
- Avoid ACE inhibitors and ARBs—these are contraindicated in pregnancy due to fetotoxicity 3