In the months following childbirth, there are abrupt and dramatic changes in hormone levels which can play a role in PPD (postpartum depression). Overlapping hormones in my research thus far linked with PPD include imbalances of progesterone, estrogen, prolactin, cortisol, oxytocin, and thyroid. This is by no means a complete list.
The rise in some of the above listed hormones increases during pregnancy, peaks at delivery and then drops off postpartum. Consuming the placenta could offer a tapering effect of depleting hormone levels.
PPD is common- about ⅓ of mothers experience some form of PPD. A mother suffering from PPD may have a negative outlook on motherhood which can interfere with maternal-infant bonding.
Iron deficiency is a common cause of anemia which is a physiological variable as a PPD risk factor. Iron deficiency also alters thyroid hormone metabolism. Early postpartum anemia is a significant risk factor for PPD. Consuming the placenta may supplement iron for mom.
In conclusion, consuming the placenta has been traditionally practiced across most mammals and leads me to believe there is clearly some benefit to it! Whether consuming it is a placebo effect or has actual hormone and nutrient supplement benefits, it can be a safe alternative to see if it works for you. If the effects seem to not make a difference or have a negative impact, then stop consuming. There are few risks to consuming a healthy placenta postpartum.