<prompt> Oligohydroamnios is AFI-8cm5cm2 cm1 cm  <response>: Ans. is b i.e., 5 cm Oligohydramnios1 AFI 5 cm or single largest vertical pocket 2cm2 Amniotic fluid less than 100 mLEtiologyChromosomal AbnormalitiesUteroplacental Insufficiency Congenital anomalies e.g., renal agenesis and posterior urethral valves IUGR Postdatismpostterm pregnancy PROM Twin-to-twin transfusion Hypertension Preeclampsia NSAIDs, angiotensin-converting enzyme inhibitors Idiopathic 