Core Concepts: Neonatal Glomerular Filtration Rate

Abstract

Although the placenta is the primary organ responsible for fetal clearance and electrolyte homeostasis, fetal kidneys contribute to amniotic fluid production and fetal hemodynamics. Maternal factors can significantly influence fetal urinary output and blood pressure. Maturation of neonatal glomerular filtration rate (GFR) depends on the development of renal blood flow (RBF). After birth, a marked increase in systemic blood pressure and decrease in renal vascular resistance results in elevated RBF and consequent increases in GFR. Vasoactive factors, including renin, angiotensin II, glucocorticoids, nonsteroidal anti-inflammatory drugs, nitric oxide, prostaglandins, bradykinin, and endothelin, each play vital roles in the regulation and development of neonatal GFR. Prematurity and intrauterine growth restriction (IUGR) may affect renal endowment and place infants at risk for hypertension and accelerated loss of renal function later in life.