Physiologic proteinuria in labor and postpartum: The results of the postpartum proteinuria trial (PoPPy).

•Physiologic proteinuria increases after delivery, regardless of mode.•The normal increase in proteinuria in labor and postpartum may result in over diagnosis of postpartum preeclampsia.•A higher threshold for proteinuria may reduce false positive tests for preeclampsia in the immediate postpartum period.