Oligohydramnios

Oligohydramnios is a condition during pregnancy where there is too little amniotic fluid, the protective liquid surrounding the baby in the womb. This fluid is important for cushioning the baby, allowing movement, and helping lung development. When the amount of amniotic fluid is too low, it can affect the baby's growth and increase the risk of complications during delivery. The condition involves the reproductive system, specifically the uterus and placenta. It may be caused by problems with the baby's kidneys or urinary tract, placental issues, or rupture of membranes. Detecting low amniotic fluid early is important to monitor the baby's health. This condition can lead to restricted fetal movement and potential breathing difficulties after birth.

Oligohydramnios is defined as a decreased volume of amniotic fluid below the expected range for gestational age, typically less than 500 mL in the third trimester or an amniotic fluid index (AFI) less than 5 cm. It results from reduced fetal urine production, increased fluid loss through ruptured membranes, or placental insufficiency impairing fluid exchange. The core pathology involves inadequate amniotic fluid, which compromises fetal cushioning and lung development. Common causes include fetal renal anomalies, premature rupture of membranes (PROM), uteroplacental insufficiency, and post-term pregnancy. Clinically, it is significant because it increases the risk of cord compression, fetal distress, and musculoskeletal deformities. Diagnosis and management are critical to prevent adverse perinatal outcomes such as pulmonary hypoplasia and intrauterine growth restriction.