French surgeons made headlines 12 years ago when they conducted the first-ever face transplant. Now, another team has made medical history with the world's first "re-transplantation".

A 40-year-old Frenchman underwent a second face graft earlier this month after his body rejected the first transplant which he received seven years ago. The unnamed man had to have the earlier graft removed in November since which time he was without a face and had to be kept in a medically-induced coma.

"The severity of the rejection required a complete resection of the face on November 30, 2017 and the patient was since hospitalized in intensive care," France's biomedical agency and the national hospital service said in a statement released on 19 January.

The operation took close to 20 hours, starting on 15 January early afternoon and ending on 16 January early morning.

This second transplant is subjected to severe immunological constraints and only the follow-up at several weeks will confirm the viability of the graft.

More than 30 face transplants have been carried out since 2005, on people whose facial structures have been disfigured from genetic issues, violence or accidents. However, at least six people have died from the operation, with one case being a post-surgery suicide.

According to a medical paper in The Lancet from August 2016, patients' social support and pre-existing psychiatric conditions also weigh in on the risk–benefit ratio of facial transplantation.

"Careful preoperative patient selection and long-term postoperative follow-up programmes under strict institutional review board controls should be used for any future grafts of this type," the study, funded by Protocole Hospitalier de Recherche Clinique (PHRC) National stated.

Isabelle Dinoire, the woman who received the world's first face transplant, died in 2016 at the age of 49. She became ill and was diagnosed with two types of cancer after years of taking immunosuppressant drugs which were believed to be responsible for her failing health.

Around the time of her death, and over a decade after her surgery, her body started rejecting the transplant and she lost partial use of her lips.