What is the primary goal in managing hypertension in pregnancy?

Management of Hypertension in Pregnancy: Primary Goals

The primary goal in managing hypertension in pregnancy is to prevent severe maternal complications (particularly stroke, heart failure, and end-organ damage) while maintaining adequate uteroplacental perfusion to ensure fetal well-being. 1, 2

Blood Pressure Targets and Treatment Thresholds

When to Initiate Treatment

• Severe hypertension (≥160/110 mmHg): Immediate treatment required within 30-60 minutes to prevent cerebrovascular complications 1, 2
• Mild to moderate hypertension (140-159/90-109 mmHg): Treatment should be initiated for:
  • Pre-existing hypertension
  • Hypertension with end-organ damage
  • Hypertension with symptoms (headache, visual disturbances)

Optimal Blood Pressure Targets

• Target range: 110-140/85 mmHg 1, 2
• This range balances maternal protection while maintaining adequate uteroplacental perfusion
• Avoid excessive BP lowering as it may impair fetal growth 1

First-Line Medications

During Pregnancy

• First-line agents:
  • Labetalol (750 mg to 4 g per day in divided doses)
  • Extended-release nifedipine (up to 100 mg twice daily)
  • Methyldopa (particularly for long-term management) 1, 2

For Hypertensive Emergencies

• IV labetalol: First-line for severe hypertension requiring rapid control
• Oral nifedipine: Alternative when IV access not available
• IV hydralazine: Alternative option but requires close monitoring 1, 2

Contraindicated Medications

• Absolutely contraindicated:
  • ACE inhibitors
  • ARBs
  • Direct renin inhibitors 1
• Use with caution:
  • Diuretics (may reduce plasma volume)
  • Atenolol (risk of fetal growth restriction) 2

Monitoring Requirements

Maternal Monitoring

• Regular BP measurements (at least weekly in stable patients)
• Assessment for signs of preeclampsia:
  • Proteinuria (protein/creatinine ratio ≥30 mg/mmol)
  • Headache, visual disturbances
  • Epigastric pain, nausea, vomiting
  • Laboratory tests: CBC, platelets, liver enzymes, renal function 1, 2

Fetal Monitoring

• Ultrasound assessment for fetal growth every 2-4 weeks
• Amniotic fluid volume assessment
• Doppler studies if growth restriction is suspected 2

Special Considerations

Preeclampsia Management

• Add magnesium sulfate for seizure prophylaxis when preeclampsia with severe features is present
• Consider expedited delivery depending on gestational age and maternal/fetal condition 1, 2

Postpartum Management

• BP typically rises in the first 5 days after delivery
• Continue monitoring for at least 72 hours in hospital and 7-10 days postpartum
• Safe medications during breastfeeding: labetalol, nifedipine, enalapril, metoprolol
• Avoid methyldopa postpartum due to risk of depression 2

Long-Term Considerations

• Women with history of hypertensive disorders in pregnancy have increased lifetime cardiovascular risk
• Annual BP monitoring recommended
• Lifestyle modifications (weight management, regular exercise, healthy diet)
• Early preventive strategies for future pregnancies (low-dose aspirin if indicated) 2

Common Pitfalls to Avoid

1. Excessive BP lowering: May compromise uteroplacental perfusion and fetal growth
2. Delayed treatment of severe hypertension: Increases risk of stroke and other complications
3. Failure to recognize preeclampsia: Can lead to eclampsia, HELLP syndrome, and other severe complications
4. Inappropriate medication use: Using contraindicated medications like ACE inhibitors or ARBs
5. Inadequate postpartum monitoring: Many complications occur in the early postpartum period

By focusing on these goals and management strategies, clinicians can significantly reduce maternal and fetal morbidity and mortality associated with hypertensive disorders in pregnancy.