What is the management and treatment for a pregnant woman diagnosed with pre-eclampsia?

Management of Preeclampsia

Women diagnosed with preeclampsia should be delivered at 37 weeks gestation or immediately if severe features develop, while those diagnosed before 37 weeks require intensive maternal-fetal monitoring with delivery indicated for maternal organ dysfunction, uncontrolled severe hypertension, or fetal compromise. 1

Initial Assessment and Diagnosis

Confirm the diagnosis by documenting blood pressure ≥140/90 mmHg on repeat measurements and quantify proteinuria using urine protein/creatinine ratio (≥30 mg/mmol is abnormal). 1 Automated dipstick urinalysis serves as the initial screening tool. 1

Immediately evaluate for severe features including:

• Severe hypertension (≥160/110 mmHg) 1, 2
• Thrombocytopenia (platelets <100×10⁹/L) 1
• Progressive renal dysfunction (elevated creatinine) 1
• Liver involvement (elevated transaminases) 1
• Pulmonary edema 1
• New-onset severe persistent headache, visual disturbances, or right upper quadrant/epigastric pain 1, 2

Obtain baseline laboratory tests including complete blood count with platelets, liver transaminases (AST/ALT), serum creatinine, and consider uric acid. 2 Repeat these at least twice weekly or more frequently if clinical deterioration occurs. 1, 2

Blood Pressure Management

For Severe Hypertension (≥160/110 mmHg)

Initiate urgent antihypertensive therapy within 15 minutes to prevent maternal stroke, targeting systolic BP 110-140 mmHg and diastolic BP 85 mmHg. 2, 3

First-line medications:

• Oral nifedipine 10 mg, repeat every 20 minutes to maximum 30 mg 2, 3
• IV labetalol 20 mg bolus, then 40 mg after 10 minutes if needed, followed by 80 mg every 10 minutes to maximum 220 mg 3
• IV hydralazine as alternative 1, 3

Critical contraindications:

• Never use sublingual nifedipine due to risk of precipitous drops causing myocardial infarction or fetal distress 3
• Absolutely avoid ACE inhibitors, ARBs, and direct renin inhibitors due to severe fetotoxicity causing fetal renal dysgenesis 2, 3
• Do not combine IV magnesium with calcium channel blockers due to risk of myocardial depression 3
• Avoid diuretics as they further reduce plasma volume, which is already compromised in preeclampsia and worsens uteroplacental perfusion 2, 3

For Non-Severe Hypertension (140-159/90-109 mmHg)

Use oral labetalol, nifedipine, or methyldopa for blood pressure control. 1 Continue antihypertensives throughout pregnancy and postpartum, tapering slowly only after days 3-6 postpartum unless BP becomes low (<110/70 mmHg). 1

Magnesium Sulfate for Seizure Prophylaxis

Administer magnesium sulfate if severe features are present, particularly severe hypertension (≥160/110 mmHg) or neurological symptoms (headache, visual changes). 1, 2, 3

Dosing regimen: Initial IV dose of 4-5 g in 250 mL of 5% dextrose or 0.9% sodium chloride infused over 3-4 minutes, followed by maintenance of 1-2 g/hour by continuous IV infusion or 4-5 g IM into alternate buttocks every 4 hours. 4 Total daily dose should not exceed 30-40 g. 4

Therapeutic serum magnesium level of 6 mg/100 mL (2.5-7.5 mEq/L) is optimal for seizure control. 4 Monitor deep tendon reflexes and respiratory function; reflexes disappear as plasma level approaches 10 mEq/L, and respiratory paralysis may occur. 4

Critical warning: Continuous maternal administration beyond 5-7 days can cause fetal abnormalities. 4 In severe renal insufficiency, maximum dosage is 20 grams/48 hours with frequent serum magnesium monitoring. 4

Maternal Monitoring Protocol

Monitor blood pressure continuously or every 4 hours while awake. 1, 2 In the early postpartum period, continue monitoring at least every 4 hours for at least 3 days as preeclampsia can develop de novo postpartum. 1, 3

Perform clinical assessments including deep tendon reflexes, clonus evaluation, and neurological status. 1, 2 Use the PIERS model (Preeclampsia Integrated Estimate of Risk) to predict likelihood of severe adverse maternal outcomes using gestational age, chest pain/dyspnea, oxygen saturation, platelet count, serum creatinine, and aspartate aminotransferase. 1

Repeat laboratory tests at least twice weekly: hemoglobin, platelets, liver transaminases, creatinine. 1, 2 Repeat the day after delivery and then every other day until stable if abnormal before delivery. 1

Fetal Surveillance

Perform fetal biometry (biparietal diameter, head circumference, abdominal circumference, femur length), amniotic fluid volume assessment, and umbilical artery Doppler at initial diagnosis. 1, 2 Serial evaluations should occur at 2-week intervals minimum from 24 weeks until birth. 1

Initiate continuous electronic fetal heart rate monitoring to assess for non-reassuring fetal status. 2, 5 A biophysical profile including fetal breathing movements, body movements, and tone helps determine urgency and mode of delivery. 5

Fluid Management

Strictly limit total fluid intake to 60-80 mL/hour to prevent pulmonary edema. 1, 3 Replace anticipated urinary losses (0.5-1 mL/kg per hour) but avoid "running dry" as preeclamptic women are already at risk of acute kidney injury. 1

Indications for Immediate Delivery

Deliver immediately at any gestational age if any of the following develop: 1, 2, 3

• Repeated episodes of severe hypertension despite maintenance treatment with 3 classes of antihypertensive agents
• Progressive thrombocytopenia
• Progressively abnormal renal or liver function tests
• Pulmonary edema
• Abnormal neurological features (severe intractable headache, repeated visual scotomata, or eclamptic seizures)
• Non-reassuring fetal status
• Placental abruption

Deliver at 37 weeks and zero days gestation if preeclampsia is present without severe features. 1, 5 After maternal stabilization (if severe features present), prefer vaginal delivery unless cesarean is indicated for standard obstetric reasons. 5

Before delivery at <35 weeks gestation, administer high-dose dexamethasone or betamethasone per national guidance to improve fetal lung maturity. 1 If delivery required before 32 weeks, magnesium sulfate also serves as a neuroprotective agent for the fetus. 1

Prevention Strategies for Future Pregnancies

Administer low-dose aspirin (ideally 150 mg/day, minimum 75-162 mg/day) started before 16 weeks but definitely before 20 weeks in women with established risk factors including: 1

• Prior preeclampsia
• Chronic hypertension
• Pregestational diabetes mellitus
• Maternal BMI >30 kg/m²
• Antiphospholipid syndrome
• Multiple pregnancy
• Assisted reproduction pregnancy

Provide calcium supplementation (1.2-2.5 g/day) if dietary intake is low (<600 mg/day). 1 When intake cannot be assessed, it is reasonable to give calcium. 1

Encourage exercise during pregnancy—at least 3 days per week for 50 minutes using aerobic exercise, strength, and flexibility training to reduce weight gain and incidence of hypertensive disorders. 1

Do not use low molecular weight heparin to prevent preeclampsia, even with history of prior early-onset preeclampsia. 1

Postpartum Management

Continue close monitoring for at least 3 days postpartum as preeclamptic complications and eclamptic seizures may develop for the first time in the early postpartum period. 1, 3

Avoid NSAIDs for postpartum analgesia in women with preeclampsia unless other analgesics are ineffective, especially if they have known renal disease, acute kidney injury, placental abruption, sepsis, or postpartum hemorrhage. 1, 3 Use alternative pain relief as first choice. 1

Do not cease antihypertensives abruptly; taper slowly over days after day 3-6 postpartum unless BP becomes low or the woman becomes symptomatic. 1, 3

Review at 3 months postpartum to ensure BP, urinalysis, and laboratory abnormalities have normalized. 1 If proteinuria or hypertension persists, initiate appropriate referral for further investigations including work-up for secondary causes. 1

Screen for mental health complications including depression, anxiety, or post-traumatic stress disorder symptoms. 1

Long-Term Cardiovascular Risk Counseling

Counsel women that preeclampsia confers approximately 15% risk of recurrence in future pregnancies and 15% risk of gestational hypertension. 1 They have significantly increased lifetime risks of cardiovascular disease, death, stroke, diabetes mellitus, venous thromboembolic disease, and chronic kidney disease compared to women with normotensive pregnancies. 1, 3

Recommend lifelong follow-up with regular BP monitoring, periodic measurement of fasting lipids and blood sugar, maintenance of ideal weight, and regular aerobic exercise. 1, 3

Critical Pitfalls to Avoid

Do not use blood pressure level alone to determine disease severity—serious organ dysfunction can develop at relatively mild blood pressure elevations. 2

Do not use serum uric acid level or degree of proteinuria as indications for delivery. 2

Do not delay delivery at ≥37 weeks based solely on non-reactive non-stress test; at this gestational age with preeclampsia, delivery is indicated regardless of fetal testing results. 5

Do not underestimate disease severity based on "mild" classification—all preeclampsia can rapidly progress to life-threatening emergencies. 5

Recognize atypical presentations: Preeclampsia rarely occurs before 20 weeks except with trophoblastic disease (hydatidiform mole), so consider alternative diagnoses in early presentations. 2, 6