<P> The third stage of labor can be managed actively with several standard procedures, or it could be managed expectantly (also known as physiological management or passive management), the latter allowing the placenta to be expelled without medical assistance . </P> <P> Although uncommon, in some cultures the placenta is kept and consumed by the mother over the weeks following the birth . This practice is termed placentophagy . </P> <P> As the fetal hypothalmus matures activation of the HPA axis (hypothalmic - pituitary - adrenal axis) initiates labour though two hormonal mechanisms . The end pathway of both mechanisms leads to myometrial contractions a mechanical cause of placental separation, from the shear force, contractile and involution changes in the uterus distorting the placentome . </P> <Ul> <Li> ACTH increases fetal cortisol, which acts by two mechanisms: </Li> </Ul>

How does the placenta detaches from the uterus after birth
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