Tina Turner has revealed that she underwent a kidney transplant with an organ donated by her husband.

The 78-year-old singer says in an upcoming autobiography that she has suffered from kidney disease, and by 2016 her kidneys were at "20 percent and plunging rapidly."

She says her husband, Erwin Bach, "shocked me by saying that he wanted to give me one of his kidneys." Turner says she was "overwhelmed by the enormity of his offer."

Turner, whose hits include "Proud Mary" and "What's Love Got to do With It?," married German music executive Bach in 2013 after a long relationship.

Extracts from "Tina Turner: My Love Story" were released Saturday by publisher Penguin.

In the book, Turner encourages people to sign up to donate organs.