Is a pregnant woman at 35+ weeks of gestation with severe hypertension indicated for an elective cesarean section (CS)?

Management of Severe Hypertension at 35+ Weeks of Pregnancy

For a pregnant woman at 35+ weeks gestation with severe hypertension (160/100 mmHg), vaginal delivery should be considered rather than elective cesarean section unless there are standard obstetric indications for cesarean delivery. 1, 2

Immediate Management of Severe Hypertension

• Blood pressure ≥160/110 mmHg lasting >15 minutes requires urgent treatment in a monitored setting regardless of delivery plans 1, 2
• First-line treatments for acute severe hypertension include:
  • Oral nifedipine
  • Intravenous labetalol
  • Intravenous hydralazine 1, 2
• Target blood pressure should be <160 mmHg systolic and around 85 mmHg diastolic to reduce the likelihood of developing severe maternal complications 1, 2
• Magnesium sulfate should be administered for convulsion prophylaxis in women with preeclampsia who have severe hypertension with neurological signs or symptoms 1, 2

Delivery Decision-Making at 35+ Weeks

• Women with preeclampsia should be delivered if they have reached 37 weeks' gestation 1
• For women at 35-37 weeks with severe hypertension, an expectant conservative approach may be considered if the condition is stable 1, 2
• Vaginal delivery should be considered for women with hypertensive disorders unless cesarean delivery is required for standard obstetric indications 1, 2
• Blood pressure should be controlled before, during, and after delivery to keep SBP <160 mmHg and DBP <110 mmHg 1, 2

Indications for Immediate Delivery (Regardless of Delivery Method)

Immediate delivery is indicated if any of the following develop:

• Repeated episodes of severe hypertension despite maintenance treatment with 3 classes of antihypertensive agents 1
• Progressive thrombocytopenia 1
• Progressively abnormal renal or liver enzyme tests 1
• Pulmonary edema 1
• Abnormal neurological features (severe intractable headache, repeated visual scotomata, or convulsions) 1
• Non-reassuring fetal status 1
• Maternal pulse oximetry <90% 1, 2
• Placental abruption 1, 2

Specific Considerations for Mode of Delivery

• The presence of severe hypertension alone is not an indication for cesarean section 1, 2
• Cesarean section should be performed for:
  • Standard obstetric indications
  • Need for rapid delivery due to maternal or fetal deterioration
  • Evidence of placental insufficiency with fetal compromise 1, 2
• Studies suggest that induction of labor at 38 or 39 weeks in women with chronic hypertension may prevent severe hypertensive complications without increasing the risk of cesarean delivery 3

Monitoring During Labor and Delivery

• Continuous blood pressure monitoring is recommended during labor and delivery 2, 4
• Maternal monitoring should include repeated assessments for proteinuria if not already present, clinical assessment including clonus, and blood tests for hemoglobin, platelet count, liver transaminases, creatinine, and uric acid 1
• Fetal monitoring should include assessment of fetal biometry, amniotic fluid, and umbilical artery Doppler with ultrasound 1

Postpartum Management

• Antihypertensive treatment should be continued during labor, delivery, and postpartum 1, 4
• All women with hypertension in pregnancy should have their blood pressure and urine checked at 6 weeks postpartum 1, 4
• Persistent hypertension should be confirmed by 24-hour ambulatory monitoring 1, 4
• Women with persisting hypertension or proteinuria at 6 weeks should be referred to a specialist 1, 4

Common Pitfalls to Avoid

• Delaying treatment of severe hypertension increases risk of stroke and other complications 2
• Attempting to diagnose mild versus severe preeclampsia clinically as all cases may become emergencies, often rapidly 1
• Using serum uric acid or level of proteinuria as an indication for delivery 1
• Using ACE inhibitors, ARBs, or direct renin inhibitors during pregnancy due to fetotoxicity 2