Table 1 Definition of the inclusion criteria for recruitment into the PREP study

New-onset pre-eclampsia

New-onset hypertension (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg on 2 occasions 4–6 h apart in women) after 20 weeks of pregnancy and new-onset proteinuria (≥2+ in urine dipstick or PCR of greater than 30 mg/mmol or 300 mg of protein excretion in 24 h) [37]

Suspected pre-eclampsia

New-onset hypertension (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg on 2 occasions 4–6 h apart in women) after 20 weeks of pregnancy and 1+ proteinuria on urine dipstick

Superimposed pre-eclampsia

- In women with chronic hypertension and no proteinuria before 20 weeks’ gestation

New-onset proteinuria (as defined previously)

- In women with significant proteinuria before 20 weeks’ gestation

Elevated serum alanine aminotransferase concentration (>70 U/L) or worsening hypertension (either 2 diastolic BP of at least 110 mmHg 4 h apart or 1 diastolic measurement of at least 110 mmHg if the woman had been treated with an anti-hypertensive drug), plus one of the following: increasing proteinuria, persistent severe headaches or epigastric pain

HELLP syndrome

Haemolysis, elevated liver enzymes, and low platelets syndrome: presence of haemolysis based on examination of the peripheral smear, elevated indirect bilirubin levels or low serum haptoglobin levels in association with significant elevation in liver enzymes and a platelet count below 100,000/mm³ after ruling out other causes of haemolysis and thrombocytopenia

1 episode of eclamptic seizures without hypertension or proteinuria

Other neurological conditions of seizures have been excluded