Table 1.

Commonly used diagnostic criteria and classification of hypertensive disorders of pregnancy. The pregnancy-specific conditions may also be diagnosed where diastolic pressure exceeds 90 mmHg but systolic pressure is < 140 mmHg. It is usual to exclude the diagnosis if hypertension is recorded only during labour.

Classification	Diagnostic criteria
Gestational hypertension	Hypertension: blood pressure ≥ 140/90 mmHg after 20th week of pregnancy in a previously normotensive woman.
Pre-eclampsia	Hypertension: blood pressure of ≥ 140/90 mmHg after 20th week of pregnancy in a woman who was previously normotensive.
	Proteinuria: urinary excretion ≥ 300 mg/L or 500 mg/24 h in the absence of urinary tract infection.
Eclampsia	Occurs in a woman with pre-eclampsia.
	Characterised by seizures not attributed to other causes.
Superimposed pre-eclampsia	Chronic hypertension with development of proteinuria during pregnancy.
Chronic hypertension	Hypertension present before 20th week of pregnancy, persistent for more than 6 weeks postpartum, or both.