Childbirth refers to all the events that are necessary to expel the foetus from the mother’s womb. In humans, childbirth normally occurs between the 38th and the 41th gestation week. Childbirth is categorised in three stages: from the start of the labour to the complete dilatation of the cervix (dilatation phase); from the complete dilatation to the actual delivery (foetal expulsion); from the childbirth to the passage of the placenta (discharge of the afterbirth). The start of the labour corresponds to the beginning of contractions, which are associated to the anatomic modifications of the cervix, with the thinning and stretching of the cervix, that allow the child to be delivered. During the first stage, spontaneous rupture of the membranes also occurs, otherwise it is provoked artificially via amniotomy. Towards the middle of the dilatation phase, once a dilation of 3-4 cm is reached, the epidural injection can be performed to relieve the mother from some pain. When the cervix is completely dilated and the child passes through the cervix, the foetal expulsion phase begins, i.e. when pushing starts. Once the child has been delivered, the umbilical cord is cut and the placenta is expelled during the discharge of the afterbirth phase, the last one.
Childbirth has potential complications, such as vaginal bleeding, abnormal foetal heart rate and abnormal foetal positions (breech birth). However, thanks to the medical progress, the problems that used to cause the death of the child or of the mother are today very rare. The baby is constantly monitored and in case of complications the caesarean section is practiced. Preterm delivery – between the 20th and the 37th week – is instead more problematic. Premature babies risk suffering from cerebral, respiratory and digestive problems, and mortality in the first days after birth is very high. For centuries, women in labour have relied on the experience of midwives - and it still happens in the rural areas of developing countries - whereas today they can rely on the assistance of specialised teams, depending on the customs and beliefs of the different countries. Despite the risks and the pain, women have faced childbirth ever since the beginning of time, ensuring the survival of the human race.