Amniocentesis is legally used for determining

Amniocentesis is a withdrawal of a sample of the fluid (amniotic fluid) surrounding an embryo in the uterus by piercing the amniotic sac through the abdominal wall. As the amniotic fluid contains cells from the embryo (mostly shed from the skin), cells cultures enable chromosome patterns to be studied so that prenatal diagnosis of chromosomal abnormalities (such as Down's syndrome) can be made, metabolic errors and other diseases, such as spina bifida, can also be diagnosed prenatally from the biochemistry of the cells or that of the fluid.