What is the management approach for a pregnant individual at 38 weeks gestation with hypertension?

Management of Elevated Blood Pressure at 38 Weeks Gestation

At 38 weeks gestation with elevated blood pressure, immediate delivery should be planned after initial assessment and stabilization, as this gestational age meets the threshold for delivery in any hypertensive disorder of pregnancy. 1, 2

Immediate Assessment and Classification

Blood Pressure Measurement

• Confirm hypertension with repeat measurements: BP ≥140/90 mmHg defines hypertension in pregnancy 1
• If BP is severe (≥160/110 mmHg), confirm within 15 minutes and initiate urgent treatment 1
• For less severe elevations, repeat measurements over a few hours to confirm persistent hypertension 1

Determine Hypertensive Disorder Type

The classification depends on timing and associated features:

• Gestational hypertension: New-onset hypertension after 20 weeks without proteinuria or end-organ dysfunction 1
• Preeclampsia: Hypertension plus proteinuria (≥30 mg/mmol on protein/creatinine ratio) OR evidence of maternal organ dysfunction (thrombocytopenia, renal insufficiency, liver involvement, pulmonary edema, or neurological symptoms) 1, 3
• Chronic hypertension with superimposed preeclampsia: Pre-existing hypertension with new-onset proteinuria or worsening features 1

Initial Laboratory Workup

Obtain immediately to assess for preeclampsia and severity:

• Complete blood count focusing on hemoglobin and platelet count 1, 2
• Liver transaminases (AST, ALT) 1, 2
• Serum creatinine and uric acid 1, 2
• Urine protein/creatinine ratio (≥30 mg/mmol or 0.3 mg/mg indicates significant proteinuria) 1, 2

Blood Pressure Management

Severe Hypertension (≥160/110 mmHg)

Urgent treatment is required in a monitored setting when BP reaches ≥160/110 mmHg to prevent maternal stroke and other complications. 1

First-line medications:

• Oral nifedipine: Preferred for rapid onset and ease of administration 1
• Intravenous labetalol: Alternative first-line agent 1, 2
• Intravenous hydralazine: Alternative if above agents unavailable 1

Target blood pressure: Systolic 110-140 mmHg and diastolic 85 mmHg 1, 2

Critical caveat: Avoid excessive blood pressure reduction below diastolic 80 mmHg, as this may compromise uteroplacental perfusion; reduce or cease antihypertensives if diastolic falls below this threshold 1

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

Treatment is recommended for persistent BP ≥140/90 mmHg to reduce progression to severe hypertension:

• Oral methyldopa, labetalol, nifedipine, or oxprenolol are acceptable first-line agents 1
• Target diastolic BP of 85 mmHg (systolic 110-140 mmHg) 1

Magnesium Sulfate for Seizure Prophylaxis

Administer magnesium sulfate if the patient has preeclampsia with any of the following features:

• Proteinuria plus severe hypertension (≥160/110 mmHg) 1
• Any hypertension with neurological signs or symptoms (severe headache, visual disturbances, hyperreflexia with clonus) 1, 2

Dosing regimen:

• Loading dose: 4-5g IV over 5 minutes 4
• Maintenance: 1-2g/hour continuous IV infusion 4
• Continue through delivery and for at least 24 hours postpartum 1

Important warning: Do not administer magnesium sulfate concomitantly with calcium channel blockers (nifedipine) due to risk of severe hypotension from synergistic effects 1, 5

Maternal Monitoring Requirements

Clinical Assessment

• Continuous blood pressure monitoring 2
• Assessment for deep tendon reflexes and clonus 1
• Evaluation for symptoms: severe headache, visual disturbances, right upper quadrant pain, shortness of breath 2
• Urine output monitoring (oliguria is a warning sign) 1

Laboratory Monitoring

Repeat at least twice weekly or more frequently if clinical deterioration:

• Hemoglobin and platelet count 1
• Liver enzymes, creatinine, and uric acid 1
• Reassess for proteinuria if not initially present 1

Fetal Assessment

Initial Evaluation

• Electronic fetal heart rate monitoring to assess fetal well-being 2
• Ultrasound for fetal biometry, amniotic fluid volume, and umbilical artery Doppler 1, 2

Ongoing Surveillance

If delivery is delayed for any reason (though unlikely at 38 weeks):

• Serial fetal surveillance every 2 weeks if initial assessment normal 1
• More frequent monitoring if fetal growth restriction identified 1

Delivery Planning

At 38 weeks gestation, delivery is indicated regardless of the specific hypertensive disorder or severity, as this exceeds the 37-week threshold for delivery in all cases of preeclampsia and gestational hypertension. 1, 2

Timing

• Immediate delivery after maternal stabilization with blood pressure control 2, 4
• Do not delay delivery for expectant management at this gestational age 1

Mode of Delivery

• Vaginal delivery is preferred unless cesarean indicated for standard obstetric reasons 4
• Induction of labor is appropriate 1

Absolute Indications for Immediate Delivery (if not already planned)

Even before 37 weeks, delivery would be mandated by:

• Uncontrolled severe hypertension despite 3 antihypertensive classes 1
• Progressive thrombocytopenia 1
• Progressively abnormal liver or renal function tests 1
• Pulmonary edema 1
• Severe neurological features (intractable headache, visual scotomata, eclamptic seizures) 1
• Non-reassuring fetal status 1

Critical Pitfalls to Avoid

1. Do not use methyldopa for urgent blood pressure reduction—it has slow onset and is inappropriate for acute management 1

2. Do not rely on proteinuria level or uric acid to guide delivery decisions—these do not correlate with outcomes and should not delay delivery at 37+ weeks 2

3. Do not assume gestational hypertension is benign—at least 25% will progress to preeclampsia, requiring close surveillance 1

4. Do not administer plasma volume expansion routinely—this is not recommended and may worsen outcomes 1, 2

5. Recognize that preeclampsia can worsen or initially present postpartum—maintain close monitoring for 72 hours after delivery 3

6. Be aware that blood pressure alone does not indicate severity—serious organ dysfunction can develop at relatively mild BP elevations 2