The first stage the cervix, or neck of the womb, opens up to make space for the baby. It needs to open to approximately 10 centimetres before the baby's head can pass through. This is called dilation of the cervix.
The second stage the baby passes through the last few inches of the birth canal and is pushed right out of the mother's body.
The third stage the placenta, the rest of the umbilical cord and the membranes come down through the birth canal and are delivered.