Many providers supply special containers for placenta disposal to allow safe containment and transport to a disposal point. Incineration is the usual process. If stored in a freezer, several pharmaceutical companies will collect these for reserach or drug (hormone) extraction though in these days of genetic modification most of the hormone products can be produced by more modern, and safer, techniques.

In practice, it is quite common for mothers to want to take their placenta and bury it in the garden; some even slice, cook and eat it!

And in the US, concern about the welfare of babies after several placentae were thrown into a river (all the babies were several years old and doing well) caused problems for Police.   The woman in question told police she had stored the placentas for several years and finally decided the river was where she wanted to place them.

While we concern ourselves with the safety issues of clinical wastes and tiussue wastes in particular,  the days of the placenta being carted out as medical waste are long past us. There are women practicing placentophagy — making meatloaf and scarfing placenta pills, which some experts claim will help ward off postpartum depression. We’ve heard of taking it home to bury in the backyard (sometimes called “planting” the placenta) and of course making teddy bears. And a new one that’s come up recently: making placenta art — throwing it on a piece of paper and framing the resulting splatter.

http://thestir.cafemom.com/pregnancy/111122/placenta_hoarder_decides_to_clean