Ick!
Cant imagine it has any more nutritional value than any of your other viscera.
Once the blood flow between it and you stop it is a dead organ.
Its done its job - End of.
Burying it with some reverence as many cultures do makes far more sense than ingesting it to me.
Feed it to your roses much more benefit from it that way.
Leaving it attached to the baby is also another practice I find rather gruesome - its dead, why have a piece of rotting flesh attached to your precious baby for x many days.
Mammals chew through the umbilical cord or it breaks naturally shortly after delivery, for a very good reason. It needs to be got rid of so it doesn't attract predators.
Yes some eat it as an immediate means to dispose of and probably regain any nutritional value, but surely we have gone beyond needing to do that?
There was a program about it, women saying that chimps don't remove it, but research says its usually inexperienced first time mothers that often leave it attached.
Cook it if you have to eat it. Steak and placenta pie - yummy 