Renal agenesis is an inborn condition in which an infant is born without one or both kidneys. The absence of one kidney at birth is called unilateral renal agenesis; while the absence of both kidneys is called bilateral renal agenesis.

The most common form of renal agenesis is unilateral, in which an infant is born without one kidney. Unilateral renal agenesis usually does not pose significant risk, as long as the other kidney remains healthy. Adults with unilateral renal agenesis have more risk of developing hypertension and high blood pressure, and are often advised against playing contact sports. Bilateral renal agenesis, the absence of both kidneys at birth, is more uncommon yet generally considered to be more serious or severe. The absence of both kidneys in a fetus causes Oligohydramnios (or deficiency of amniotic fluid) in the mother during pregnancy. Under normal circumstances, the mother's amniotic fluid serves as a cushion for the developing fetus. However, when there is an insufficiency of this fluid, there is more risk of the fetus getting compressed and suffering from further malformations.

Renal agenesis, either unilateral or bilateral, is a congenital condition marked by the kidney's deficiency or failure to develop in a fetus. Renal agenesis is more common in the offspring of a patient with a kidney malformation. One in three infants born with this genetic defect are still born; those born alive usually do not last beyond four hours.

renalagenesis