Current investigations into pre-eclampsia centre on possible prophylaxis with low-dose aspirin. Therapy with methyldopa has beneficial effects on maternal blood pressure and also on placental perfusion. Some evidence is found for central anticonvulsant actions of magnesium sulphate. Monitoring blood pressure in pre-eclampsia using automatic oscillometry gives diastolic readings of about 10 mmHg lower than with auscultation, thus presenting diagnostic exactitude.