You guys wanna do some babies?; BABY AS DRUG

A placental tissue of foetal origin — i.e. the syncytiotrophoblast — excretes beta-endorphins into the maternal blood system from the 3rd month of pregnancy. A recent study [24] proposes an adaptive background for this phenomenon. The authors argue that foetuses make their mothers endorphin-dependent then manipulate them to increase nutrient allocation to the placenta. Their hypothesis predicts that: (1) anatomic position of endorphin production should mirror its presumed role in foetal-maternal conflict; (2) endorphin levels should co-vary positively with nutrient carrying capacity of maternal blood system; (3) postpartum psychological symptoms (such as postpartum blues, depression and psychosis) in humans are side-effects of this mechanism that can be interpreted as endorphin-deprivation symptoms; (4) shortly after parturition, placentophagy could play an adaptive role in decreasing the negative side-effects of foetal manipulation; (5) later, breast-feeding induced endorphin excretion of the maternal pituitary saves mother from further deprivation symptoms. These predictions appear to be supported by empirical data.[24]