A team of South African doctors have successfully performed the world's first penis transplant on a 21-year-old man whose organ had been amputated three years ago after a botched circumcision.

The nine-hour operation, which took place in December, was part of a pilot study by Tygerberg Hospital in Cape Town and the University of Stellenbosch to help the 250 or so young South African men who lose their penises each year after coming-of-age rituals go wrong.

Doctors said the patient, who was not named, had already recovered full urinary and reproductive functions, and that the procedure could eventually be offered to men who have lost their penis to cancer or as a last resort for severe erectile dysfunction.

"Our goal was that he would be fully functional at two years and we are very surprised by his rapid recovery," Andre van der Merwe, the head of the university's urology unit who led the operation, said in a statement.

Another nine patients have now been lined up to have the operation.

Each year thousands of young South African men, mainly from the Xhosa tribe, mark their passage into manhood by shaving their heads and smearing themselves with white clay from head to toe, living in special huts away from the community for several weeks, and then undergoing ritual circumcision.

But in May 2013, more than 20 youths died after initiation rituals in the northerly Mpumalanga province, prompting rare cross-party calls for reform of a traditional practice.

A few months later, police made several arrests on suspicion of murder after 30 young men died in coming-of-age rituals in rural Eastern Cape.

Unlawful circumcisions have been known to injure up to 300 young men across the province in the space of a week.

The South African government has promoted medical circumcisions over the less safe traditional practices.

Last year, the Department of Health said it was studying a non-surgical, disposable circumcision device that it believed could also provide a safer alternative.

The Israeli device, PrePex, has been endorsed by the World Health Organisation.

It has been piloted at several non-profit sites across South Africa but has not yet been introduced in government hospitals.

Reuters