Oligohydramnios

Oligohydramnios is a medical condition in pregnancy characterized by a deficiency of amniotic fluid in the amniotic sac, with the limiting case, anhydramnios, being a complete absence of amniotic fluid. It is typically diagnosed by ultrasound when the amniotic fluid index measures less than 5 centimeters or the single deepest pocket of fluid measures less than 2 centimeters; amniotic fluid is necessary for normal fetal movement, lung development, and cushioning, and low levels can be attributed to a maternal, fetal, placental, or idiopathic cause and can result in poor fetal outcomes including death.