Unwind

Unwind is a dystopian novel by Neal Shusterman. Unwind takes place in a future version of the United States. After the Second Civil War was fought over abortion, a compromise was reached, "The Bill of Life", a set of constitutional amendments allowing parents to sign an order for their children between the ages of 13 and 18 to be "unwound" — often taken to "harvest camps". The child's body would be dismembered and used as surgical or cosmetic transplants, essentially making conventional surgery redundant. The reasoning is that since 99.44% of the child's body is used, Unwinds do not technically die because their individual body parts live on.