Quoting SwanFoundNemo:" Absolutely not. What purpose would carrying around the placenta for a week serve? I can see letting the ... [snip!] ... the cord pulse until done, that makes sense...but carrying around the rotting bag of baby holder. Nope, its job is done. "
It doesn't hold the baby, it's the placenta. I read some things on it, it seems you have to "take care" of the placenta to keep it from smelling, and the information I read said the cord usually falls off in 2-3 days, so you aren't carrying around anything for a week, 2-3 days after birth is usually spent in bed with your baby anyway.