Parturition, commonly known as childbirth, is a complex process involving the expulsion of the fetus from the mother’s uterus. It occurs in three main stages: dilation, expulsion, and after birth or placental delivery.
1. Dilation: During the dilation stage, uterine contractions gradually move the baby towards the cervix, causing pain from blood vessel compression. Strengthened by oxytocin, contractions lead to the baby’s descent, lasting a few hours and ending with cervix and vagina dilation, concluding as the foetus’s amniotic membrane ruptures.
2. Expulsion stage : The uterine and abdominal contractions become stronger. In normal delivery, the foetus passes out through cervix and vagina with head in forward direction. It takes 20 to 60 min. The umbilical cord is tied and cut off close to the baby’s navel.
3. After birth : After the baby is born, the placenta separates from the uterus and is expelled as “afterbirth” within 10 to 45 minutes due to strong uterine contractions.