Answer:
Oxytocin Hormone
Step-by-step explanation:
It is the oxytocin which is mainly responsible for contraction of womb along with lactation during child birth.
The muscles of uterine are stimulated by the oxytocin to release prostaglandins and cause further contraction.
Oxytocin also stimulates cervix ripening thereby leading to successive dilation during labour however Oxytocin, suring this time help in maintaining the high levels of oestrogen.