Childbirth is also known as labour and delivery. It is the process at end of pregnancy when one or more babies leave the uterus by passing through the vagina or by Caesarean section. The most common way of childbirth is a vaginal delivery. It involves three stages of labour: the shortening and opening of the cervix, descent and birth of the baby, and the delivery of the placenta. The first stage begins with crampy abdominal or back pain that last around half a minute and occur every 10 to 30 minutes and typically lasts 12 to 19 hours. The pain becomes stronger and closer together over time. The second stage pushing with contractions may occur and this stage lasts from 20 minutes to two hours, and the third stage five to 30 minutes. In the third stage, delayed clamping of the umbilical cord is generally recommended.