Chapter 215 Oligohydramnios
INTRODUCTION
Description: Oligohydramnios is an abnormal reduction in the amount of amniotic fluid surrounding the fetus. At term, there should be about 800 mL of amniotic fluid present.
ETIOLOGY AND PATHOGENESIS
Causes: Unknown. Generally associated with a reduction in fetal urine production (renal agenesis, urinary tract obstruction, and fetal death), chronic amniotic leak, maternal disease (hypertension, diabetes, uteroplacental insufficiency, pre-eclampsia).
DIAGNOSTIC APPROACH
Differential Diagnosis
Associated Conditions: Fetal—renal and urinary tract anomalies, intrauterine fetal growth restriction, pulmonary hypoplasia, musculoskeletal defects (clubfoot, amniotic bands, amputations), meconium-stained amniotic fluid. Fetal anomalies are present in 15% to 25% of cases. Maternal—chronic disease (diabetes, hypertension).
