Does labetalol influence the development of proteinuria in pregnancy hypertension? A randomised controlled study

Abstract It is the development of proteinuria in pregnancy-induced hypertension which is associated with an increased perinatal mortality. There is some evidence to suggest that labetalol may diminish the amount of proteinuria in patients who have already developed proteinuric pre-eclampsia. A randomised controlled study design was used to investigate whether labetalol treatment, started when a persistent diastolic blood pressure greater than 90 mmHg was observed, influenced the subsequent development of proteinuria. One hundred and fourteen women with singleton pregnancies and hypertension in the absence of proteinuria were randomised to receive either labetalol or no antihypertensive therapy. At recruitment maternal age, blood pressure and gestation were similar in both the labetalol and control groups. There was no difference in the frequency, quantity or timing of subsequent proteinuria between treatment and control groups. Overall 34% of primigravidae and 10% of parous women developed proteinuria. Labetalol did, however, control the blood pressure in 45 of the 51 treated women (88%) within 24 h. This effect was often shortlived requiring dose escalation after 3 to 5 days in the majority of cases. Labetalol was well tolerated and no significant maternal toxicity was noted.