The amniotic fluid is a clear, slightly yellowish liquid that surrounds the fetus during the pregnancy. The fetus floats around in the fluid, which circulates as the baby swallows and inhales the fluid, and then releases it. The amniotic fluid helps by the allowing the developing baby to move around in the womb which helps proper bone growth, as well as helping the lungs to develop properly. The fluid also keeps a constant temperature around the fetus, protecting it from heat loss, it also protects the baby from outside injury by cushioning sudden blows or movements. If the sac has too much fluid, it can cause problems when the baby is born or gestational diabetes, this is called polyhydramnios, it mostly occurs with multiple pregnancies (twins
