What is the recommended management for gestational hypertension (new‑onset hypertension after 20 weeks gestation without proteinuria)?

Management of Gestational Hypertension

For gestational hypertension (new-onset hypertension ≥140/90 mmHg after 20 weeks without proteinuria or organ dysfunction), close monitoring with blood pressure surveillance, laboratory testing for progression to preeclampsia, and fetal assessment is the primary management strategy, with antihypertensive medication initiated only if blood pressure reaches ≥150/95 mmHg or ≥140/90 mmHg with concerning features. 1

Initial Diagnostic Confirmation and Classification

• Confirm the diagnosis by obtaining at least two elevated blood pressure readings on separate occasions; for severe hypertension (≥160/110 mmHg), confirm within 15 minutes, while for non-severe elevations (140-159/90-109 mmHg), repeat measurements over several hours or at consecutive visits 2, 1

• Use a manual auscultatory device or automated upper-arm cuff that has been validated specifically for pregnancy and preeclampsia (validated devices listed at www.stridebp.org) 1

• Gestational hypertension is defined as persistent new-onset hypertension developing at or after 20 weeks' gestation without proteinuria or other features of preeclampsia 1

Mandatory Baseline Laboratory Workup

Immediately obtain the following tests to establish baseline values and exclude preeclampsia: 1

• Complete blood count with hemoglobin and platelet count
• Liver transaminases (AST, ALT) and lactate dehydrogenase
• Serum creatinine, electrolytes, and uric acid
• Urinalysis with proteinuria assessment via spot urine protein-to-creatinine ratio (PCR) or albumin-to-creatinine ratio (ACR)
• A dipstick reading >1+ should be followed by quantitative assessment; ACR <30 mg/mmol excludes significant proteinuria 1

Critical caveat: These baseline values are essential because up to 25% of women with gestational hypertension will progress to preeclampsia, and you need reference values to detect this progression 1

Risk Stratification and Monitoring Intensity

• Gestational hypertension is not benign—it carries approximately 20% risk of developing preeclampsia and another 20% chance of persistent gestational hypertension 1

• The risk of complications is directly dependent on gestational age at onset; earlier onset carries higher risk 1

• After 20 weeks gestation, consider Doppler ultrasound of uterine arteries to identify women at higher risk for preeclampsia and intrauterine growth restriction 1, 3

Blood Pressure Thresholds for Antihypertensive Treatment

The treatment threshold depends on blood pressure level and presence of risk factors: 1, 4

• Do NOT routinely treat blood pressures 140-149/90-99 mmHg in uncomplicated gestational hypertension, as antihypertensive therapy for non-severe hypertension does not improve maternal or fetal outcomes 5

• Initiate antihypertensive medication at ≥150/95 mmHg according to European guidelines 1

• Initiate treatment at ≥140/90 mmHg if any of the following are present: 1, 4

  • Gestational hypertension with proteinuria (preeclampsia)
  • Subclinical organ damage
  • Maternal symptoms (headache, visual disturbances, epigastric pain)
  • Elevated uric acid levels

• Target blood pressure is 110-140/85 mmHg to reduce risk of severe hypertension without compromising uteroplacental perfusion 3

First-Line Antihypertensive Medications

When treatment is indicated, choose from three first-line agents: 4, 6, 7

Methyldopa (Preferred First-Line)

• Start with 250 mg three times daily, titrate up to 750 mg to 4 g per day in three or four divided doses based on blood pressure response 4
• Has the longest safety record with adequate infant follow-up data (7.5 years) 4
• Recommended as first-line by European Society of Cardiology due to extensive safety record and no evidence of adverse effects on mothers or babies 4

Labetalol (Alternative First-Line)

• Start with 100 mg twice daily, can be increased up to 2400 mg/day 4
• Acceptable alternative, particularly for patients who cannot tolerate methyldopa 4
• Extensive use in pregnancy with no association with teratogenicity 4
• FDA warning: Small amounts (approximately 0.004% of maternal dose) are excreted in breast milk; hypotension, bradycardia, hypoglycemia, and respiratory depression have been reported in infants of mothers treated during pregnancy 8

Nifedipine (Long-Acting)

• Alternative for first-line therapy in non-severe hypertension 4
• Never give sublingually or intravenously due to risk of excessive blood pressure reduction causing myocardial infarction or fetal distress 4
• FDA warning: Pregnancy Category C; embryotoxic and fetotoxic effects seen in animal studies; careful monitoring required when combined with IV magnesium sulfate due to risk of excessive blood pressure fall 9

Absolutely contraindicated: ACE inhibitors, ARBs, and direct renin inhibitors due to severe fetotoxicity 3, 6

Ongoing Surveillance Strategy

Implement intensive monitoring to detect progression to preeclampsia: 1, 3

• Home blood pressure monitoring using pregnancy-validated devices for ongoing surveillance 3
• Weekly or twice-weekly clinic visits depending on blood pressure control and gestational age
• Repeat laboratory testing (complete blood count, liver enzymes, creatinine, proteinuria) at each visit or weekly to detect early signs of preeclampsia 1, 3
• Serial fetal assessment with non-stress testing and ultrasound for growth beginning at 26-28 weeks if uric acid is elevated or other concerning features develop 3

Immediate Hospitalization Criteria

Admit immediately if any of the following develop: 3

• Blood pressure ≥160/110 mmHg (severe hypertension)
• New-onset proteinuria (progression to preeclampsia)
• Severe headache, visual disturbances, or neurological symptoms
• Laboratory abnormalities suggesting preeclampsia: thrombocytopenia (platelets <100,000), elevated liver enzymes (>2x normal), rising creatinine
• Epigastric or right upper quadrant pain
• Pulmonary edema

Management of Severe Hypertension (≥160/110 mmHg)

This is a hypertensive emergency requiring urgent treatment within 15 minutes to 1 hour to prevent hemorrhagic stroke: 3, 5

• IV labetalol (first-line for acute management)
• Oral nifedipine (immediate-release acceptable in this setting)
• IV hydralazine (alternative)
• Target blood pressure of 140-150/90-100 mmHg (not normotensive, to avoid compromising placental perfusion) 3

Delivery Timing

Delivery planning depends on blood pressure control and development of preeclampsia: 3, 5

• If blood pressure remains controlled and no preeclampsia develops: Delivery can be delayed until 39 weeks + 6 days with reassuring fetal monitoring 3

• If preeclampsia develops: Deliver at ≥37 weeks' gestation 3, 5

• Earlier delivery indicated for: 3

  • Severe hypertension despite multiple antihypertensive agents
  • Progressive thrombocytopenia
  • Progressively abnormal liver or renal function tests
  • Pulmonary edema
  • Severe neurological features
  • Non-reassuring fetal status

• Expectant management may be considered in select cases of severe preeclampsia before 32 weeks' gestation in tertiary centers with intensive monitoring 10

Magnesium Sulfate for Seizure Prophylaxis

• NOT routinely indicated for gestational hypertension without severe features 5, 10

• Administer magnesium sulfate during labor and for at least 24 hours postpartum if severe preeclampsia develops or if blood pressure reaches severe range 10

Postpartum Management

• Close monitoring in early postpartum period is critical—hypertensive disorders can worsen or initially present after delivery and account for up to 44% of pregnancy-related deaths in the first six days postpartum 5

• Evaluate proteinuria at 3 months postpartum to determine if hypertension has resolved or represents chronic hypertension 2

• Gestational hypertension typically resolves within 6 weeks postpartum; persistence beyond this suggests chronic hypertension 1

Prevention Considerations for Future Pregnancies

• Women with gestational hypertension have increased risk of hypertensive disorders in subsequent pregnancies and long-term cardiovascular disease 7, 5

• For future pregnancies, if high-risk features develop (history of preeclampsia, chronic kidney disease, autoimmune disease, diabetes), recommend low-dose aspirin 75-162 mg daily starting at 12-16 weeks' gestation (ideally before 16 weeks) 1, 5

• Oral calcium supplementation 1.5-2 g/day is recommended for women with low dietary calcium intake (<600 mg/day) 1

1, 4, 3, 2, 8, 9, 6, 7, 5, 10