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  • Childbirth is also called labour, or parturition (child-birth and the expulsion of the afterbirth), and induced by a complex neuroendocrine mechanism.
  • Average duration of human pregnancy is about nine months which is called the gestation period.
  • Repeated forceful contraction of the uterus at the end of pregnancy causes expulsion/delivery of the foetus (childbirth), called as parturition.
  • Process of normal human childbirth can be classified in three stages of labour:
    • 1st Stage - complete dilation of the cervix (cervical opening widens)
    • 2nd Stage - uterine contractions occur repeatedly, baby emerges
    • 3rd Stage - expelling of afterbirth (placental expulsion) - placenta and its membranes are delivered
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