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What is Inferior vena cava syndrome and explain in detail?
Inferior vena cava syndrome (IVCS) is a very rare constellation of symptoms resulting from either an obstruction, or stenosis of the inferior vena cava. It can be caused by physical invasion or compression by a pathological process or by thrombosis within the vein itself. It can also occur during pregnancy. Pregnancy leads to high venous pressure in the lower limbs, decreased blood return to the heart, decreased cardiac output due to obstruction of the inferior vena cava, sudden rise in venous pressure which can lead to placental separation, and a decrease in kidney function.  All of these issues can arise from lying in the supine position during late pregnancy which can cause compression of the inferior vena cava by the uterus. Symptoms of late pregnancy inferior vena cava syndrome consist of intense pain in the right hand side, muscle twitching, hypotension, and fluid retention.

Signs and symptoms
IVCS presents with a wide variety of signs and symptoms, making it difficult to diagnose clinically.
Edema of the lower extremities (peripheral edema), caused by an increase in the venous blood pressure.
Tachycardia. This is caused by the decreased preload, decreased cardiac output, and leads to increased frequency.
In pregnant women, signs of fetal hypoxia and distress may be seen in the cardiotocography