THE IMPORTANCE OF NONPROTEINURIC HYPERTENSION IN PREGNANCY

Objective: To compare the prevalence of maternal and fetal complicatio ns in hypertensive Pregnant women (excluding chronic hypertension) wit h and without proteinuria. Methods: A prospective study of hypertensiv e pregnant women referred for physician care in a principal teaching h ospital between 1987 and 1993: 740 pregnant women were diagnosed as ha ving preeclampsia or gestational hypertension on the basis of (i) excl usion of essential or secondary forms of hypertension in pregnancy, (i i) hypertension arising after 20 weeks gestation and returning to norm al blood pressure after delivery. Clinical management was by one physi cian in conjunction with that patient's obstetrician, according to a u niform departmental protocol. Proteinuria was defined as greater than 300 mg/day or persistently greater than or equal to 1 g/L (i.e., 2+) o n dipstick testing if 24-h urine was unobtainable. Main Outcome Measur es: Maternal complications were: thrombocytopenia, renal insufficiency , liver disease, neurological abnormalities, and severe hypertension ( greater than or equal to 170/110 mm Hg). Fetal complications were: per inatal mortality; small for gestational age. Birth weight was recorded . Results: Only 17% had true proteinuria. Substantially more women wou ld have had this diagnosis (inaccurately) if <1 g/L (2+) on dipstick t esting alone was accepted. There was a higher prevalence of all matern al complications, and perinatal mortality was higher and birth weight lower in women with proteinuria. However, similar maternal complicatio ns still occurred in 4% to 13% of women without proteinuria. Conclusio ns: Proteinuria is associated with a greater prevalence of maternal an d fetal complications of hypertensive pregnancy. However, the absence of true proteinuria does not define a strictly benign subgroup as betw een 4% and 13% of hypertensive women without true proteinuria will als o develop these complications. The outlook for the fetus in nonprotein uric women remains very good. Thus, nonproteinuric hypertensive pregna nt patients should be managed with the same degree of vigilance as for proteinuric women.