Michael Jackson took injections to delay puberty

Jackson's former physician, (inset) Conrad Murray and Michael Jackson

Michael Jackson claimed he had been given injections at 13 to delay puberty and keep his voice high.

Jackson's former physician, (inset) Conrad Murray and Michael Jackson

The Thriller hitmaker's former personal physician, Conrad Murray - who was jailed for involuntary manslaughter after administering the fatal dose of Propofol, which killed the King of Pop in June 2009 - claimed he confided in him about the hormone treatment he had received in his early teens.

Writing in his new book, This Is It, Murray - who met Michael three years before his death - revealed: "He began talking vaguely, seeming to have more difficulty describing precisely what happened to him. Maybe he was almost at the limit to his cathartic confession that night. But what Michael said left me with the impression that he had been given injections, probably hormones, to delay puberty."

"After he had revealed for the first time to someone else his deepest held secret, Michael stopped talking," he added. Murray believes the shocking treatment accounted for his patient's bizarre character traits.

In the extract, which has been published by a newspaper, he wrote: "I often saw Jackson at his most exposed and confessional. He only agreed to share after making me swear, 'You will never breathe a word. Never.' I agreed. I was shocked when Jackson told me. It would explain all of Michael's unusual behaviour as well as his morphological changes."

In his book, Murray has also revealed that despite being renowned for his dancing skills, the singer was in constant pain because of an "advanced chronic fungal infection" and a number of callouses.