During pregnancy the foetus is supported within the uterus by a protective liquid called amniotic fluid.

The foetus and the amniotic fluid are contained within the amniotic sac (also called the amniotic cavity).

The umbilical cord is a strand of flexible tissue that carries the two umbilical arteries and umbilical vein between the foetus and the placenta.

In the newborn the umbilical cord measures about 50 cm in length.