Gestational Hypertension

New-onset hypertension (systolic ≥140 mmHg and/or diastolic ≥90 mmHg) after 20 weeks gestation, without proteinuria or other features of pre-eclampsia, distinguished from chronic hypertension (pre-existing or diagnosed before 20 weeks) and from pre-eclampsia itself.

Up to 15 to 25% progress to pre-eclampsia, which is why ongoing surveillance is essential rather than a one-time diagnosis.

Usually asymptomatic and detected on routine antenatal blood pressure measurement. Any emerging headache, visual disturbance, epigastric pain, or significant edema should prompt reassessment for progression to pre-eclampsia.

BP ≥140/90 mmHg on two occasions at least 4 hours apart after 20 weeks, with pre-eclampsia features specifically excluded, urine protein:creatinine or albumin:creatinine ratio, and bloods including LFTs, platelets, and renal function.

• Mild disease (140 to 159/90 to 109 mmHg): close monitoring with weekly to twice weekly BP and urine protein checks

• Treatment threshold BP ≥140/90 mmHg (treating to a target below 135/85 mmHg)

• First line labetalol 100 to 200 mg PO bd-tds (maximum 2400 mg/day)

• Alternatives: nifedipine modified release 10 to 20 mg PO bd (maximum 90 mg/day), or methyldopa 250 to 500 mg PO tds-qds (maximum 3 g/day). The latter is less favored now given CNS side effects but has long-standing safety data

• Severe hypertension (≥160/110 mmHg) is managed as an emergency, following the same approach detailed under Pre-eclampsia below

• Increased surveillance for progression to pre-eclampsia

• Delivery by 40 weeks if uncomplicated and well controlled; earlier if worsening