Isolated proteinuria is a risk factor for pre-eclampsia: a retrospective analysis of the maternal and neonatal outcomes in women presenting with isolated gestational proteinuria.

Abstract

To examine maternal and neonatal outcomes of isolated proteinuria and define maternal characteristics for progression to pre-eclampsia. Retrospective cohort study. Data from all hospitalized pregnant women between 2009 and 2014 with new onset isolated proteinuria of over 300 mg/24 h at admission were obtained. Follow-up was performed from the time of admission to the hospital to the time of discharge postpartum. Obstetrical, maternal and neonatal outcomes were obtained. Ninety-five pregnant women diagnosed with new onset isolated proteinuria were followed to term. Thirteen women developed pre-eclampsia during pregnancy and eight developed pre-eclampsia postpartum. Maternal characteristics for progression to pre-eclampsia were greater maximal values of proteinuria. Earlier pre-eclampsia onset was associated with early-onset proteinuria and multiple gestation. Although greater values of proteinuria were associated with increased risk for intrauterine growth restriction and lower Apgar scores, maternal outcome was favorable, regardless of pre-eclampsia progression. Isolated proteinuria progressing to pre-eclampsia was associated with late pre-eclampsia onset and favorable maternal and neonatal outcomes. A significant proportion of women with new onset isolated proteinuria will develop pre-eclampsia. In these women, close follow-up is recommended until after delivery.