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

Objective:: To examine maternal and neonatal outcomes of isolated proteinuria and define maternal characteristics for progression to pre-eclampsia. Study Design:: 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. Result:: 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. Conclusion:: 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.