The impact of proteinuria on maternal and perinatal outcomes among women with pre-eclampsia

Objective: To assess the impact of proteinuria on pregnancy outcomes among women with pre-eclampsia.

Methods: The present retrospective cohort study included patients with pre-eclampsia who delivered at a referral maternity hospital in Brazil between January 1, 2009, and December 31, 2013. Patients were stratified into three groups based on 24-hour urinary protein excretion during pregnancy: mild (0.3-<2.0 g), severe (2.0-<5.0 g), and massive (≥5.0 g).

Results: There were 293 patients included in the study; 88, 129, and 76 had mild, severe, and massive proteinuria, respectively. Chronic hypertension was the most frequent pre-existing condition among all women (86 [29.4%]). The mean pregnancy duration at the onset of maternal pre-eclampsia was longest in the mild group compared and decreased with increasing proteinuria severity (P<0.001). Preterm delivery was recorded among 205 of 293 (70.0%) neonates; there were 66 (22.5%) neonates that were preterm and in the massive proteinuria group. The incidence of severe pre-eclampsia was lowest in the mild proteinuria group (P=0.002) and tended to occur at 34 weeks. Cesarean delivery rates exceeded 80.0% in all groups. Most patients assessed at 40-60 days postpartum remained proteinuric (40/61[66%]).

Conclusions: Quantifying the severity of proteinuria could identify a subgroup of women with pre-eclampsia at increased risk of adverse outcomes.