The kidney in normal pregnancy and preeclampsia

Complicating up to 8% of pregnancies, preeclampsia is, in fact, the most common glomerular disease worldwide. In this article, we review the effect of normal pregnancy on the kidney as well as the role of the kidney in preeclampsia. We discuss blood pressure in pregnancy and preeclampsia, followed by the physiology of hyperfiltration in normal pregnancy as well as the pathophysiology of hypofiltration and proteinuria in preeclampsia. Recent studies have suggested that the clinical syndrome of preeclampsia, which recovers rapidly after delivery of the placenta, is caused by impaired vascular endothelial growth factor signaling that disturbs the status of vascular dilatation as well as the symbiosis between the glomerular endothelium and the podocytes. Finally, we discuss the intriguing association between chronic kidney disease (CKD) and preeclampsia. We hypothesize that the imbalance between angiogenic and anti-angiogenic factors, which may be common to both preeclampsia and CKD, might explain why CKD predisposes pregnant women to develop preeclampsia.