The world’s first human uterus transplant has been performed on a 26-year-old woman in Saudi Arabia. But although the organ appeared to function properly, it had to be removed after 99 days, after major clotting in associated blood vessels.
“Our clinical results with the first human uterine transplantation confirm the surgical technical feasibility and safety of this procedure,” say the team of surgeons at the King Fahad Hospital and Research Center in Jeddah. They think refinements to the surgical procedure should overcome the blood supply problems.
But other experts are unconvinced. “The uterus is a very dynamic and complex organ, and it is hugely blood-flow dependent,” says David Barlow, editor of the journal Human Reproduction and director of the assisted reproduction unit at the John Radcliffe Hospital in Oxford, UK. “It is supplied by four blood vessels, which are very small by transplant standards, giving more scope for blood clotting.”
Vessels connected to a transplanted uterus would have to cope with a massive increase in blood flow during pregnancy, he adds: “All these are major hurdles to overcome.”
The woman had her own uterus removed when she was 20, following severe bleeding after a caesarian section. The donor was a 46-year-old with ovarian cysts, who was advised to have a hysterectomy.
The procedure was performed in April 2000, but details have only now been released.
Richard Smith at the Chelsea and Westminster Hospital in London says he hopes to conduct similar experiments. Uterus transplants could offer hope to women with severe womb defects, or those, like the Saudi recipient, who haemorrhage so severely during childbirth that their wombs are removed.
The Saudi doctors gave their patient immuno-suppressants to help prevent rejection of the organ. Organ recipients need to take such drugs for the rest of their lives. But Smith says women could receive a uterus transplant, have children, and then have the organ removed.
Louis Keith, assistant editor of the International Journal of Gynecology and Obstetrics, in which the Saudi research was published, says the hysterectomy after 99 days was “not the equivalent of a clinical failure, as the uterus had previously demonstrated its ability to respond to combined estrogen-progesterone treatment.”
This hormone treatment kick-started the uterus into action, triggering the development of a normal lining and menstruation.
But 99 days after the transplant, doctors found the blood supply to the organ had stopped. They suggest this was caused by a failure to properly support the new uterus in the body, leading to twisting and kinking of the connected blood vessels and to clotting.
They say organ rejection did not contribute to the problem. But, Barlow says: “At this number of weeks into a transplant, you wonder whether rejection may have been involved in the blood clotting – it could have been partly responsible.”
Journal reference: International Journal of Gynecology and Obstetrics (vol 76, p 245)