State from where do the signals of the parturition arrives in human female??.??.??.

Dear Student, 

The signals for parturition originates from fully developed foetus and placenta which induce mild uterine contractions called foetal ejection reflex. This triggers release of oxytocin (birth hormone) from the maternal pituitary gland. The oxytocin starts a series of powerful contractions in the uterus to help expel the baby and limits bleeding of the placenta near the entry of the vaginal canal.

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