amniotic fluid and its abnormality

While a fetus is in the uterus , it is situated within the amniotic sac, a bag formed of two membranes (the amnion and the chorion) in which the fetus grows and develops. Inside the sac, the fetus is surrounded by amniotic fluid.
Amniotic fluid is vital to the healthy growth and development of a fetus.

Initially, the fluid is comprised of water produced by the mother. It is soon entirely replaced by fetal urine (as it swallows and excretes the fluid), however, around 20 week s gestation.

Amniotic fluid is not only comprised of urine, it also contains vital components such as nutrients, hormones and infection-fighting antibodies.

Too little amniotic fluid (oligohydramnios) can be a cause or an indicator of problems for the mother and baby. The majority of pregnancies proceed normally and the baby is born healthy, but this isn t always the case. Babies with too little amniotic fluid can develop contractures of the limbs, clubbing of the feet and hands, and also develop a life-threatening condition called hypoplastic lungs. If a baby is born with hypoplastic lungs, which are small underdeveloped lungs, this condition is potentially fatal and the baby can die shortly after birth due to inadequate oxygenation. Potter sequence refers to a constellation of findings related to insufficient amniotic fluid and includes shortened and malformed limbs with clubbed feet and the underdeveloped lungs that can lead to perinatal death.
The opposite of oligohydramnios is polyhydramnios, an excess volume of amniotic fluid in the amniotic sac.