Uterine transplants may not be far off

‘Uterus transplant could be tomorrow’
11 November 2006 by Phil Mckenna
New Scientist Magazine issue 2577

“IF A person walked in tomorrow and requested a uterine transplant, I am cautiously optimistic that we could be successful.” So says Giuseppe Del Priore, of New York Downtown Hospital, who has approval for such a transplant from the hospital’s review board. He has potential donors lined up, and is interviewing women who would like to receive a donated uterus.

Thousands of women with perfectly good ovaries but lacking a functioning uterus would be interested. If a uterus transplant was carried out tomorrow, it would only be the second ever. Would it be safe? The first was in Saudi Arabia in 2000 and it failed.

Last month Del Priore and colleagues at the University of Pittsburgh’s primate research laboratory performed the first successful uterus transplant in a non-human primate. The recipient was a rhesus monkey and while it was only monitored for 20 hours its new uterus had a healthy blood supply and the drugs to prevent organ rejection appeared to be working.

Del Priore now plans to follow a pregnancy in such a monkey although he says it is not strictly necessary since enough work has been done to consider it a safe procedure for women. Face transplants, for example, were not first tried in other primates.

Not everyone shares his optimism – given the complex blood vessels that supply the uterus, the dramatic growth it undergoes during a pregnancy, and the possible effects of immunosuppressants on a fetus.

In September, Richard Smith, a gynaecologist at London’s Hammersmith Hospital, claimed he was two years away from carrying out a uterine transplant. And Mats Brännström of Gothenburg University, Sweden, who has been working on uterine transplants for six years, says, “We have to do a lot more animal studies before we go on to humans.” In 2002 his group carried out the world’s only uterine transplant that led to successful pregnancy, and that was in mice.

Brännström feels that transplanting a uterus into a women before a successful pregnancy in another primate would put prospective recipients at unnecessary risk. “It may be successful, but we should continue to optimise the procedure before trying it on humans,” he says. His group is hoping to attempt transplants using a live donor, so that the woman’s mother or a close relative could be used as a donor, reducing the need for immunosuppressants.

The first human transplant failed: although the woman had two periods the transplant had to be removed after less than 100 days when a blood clot formed in the connecting blood vessels. Del Priore plans to transplant more of the original blood vessels along with the donor uterus, which he says will reduce the chances of blood clots forming, and if the organ comes from a brain-dead donor whose heart is still beating higher doses of anti-clotting drugs can be used when the uterus is removed.

Peter Bowen-Simpkins at the Royal College of Obstetricians and Gynaecologists in London isn’t convinced. “It would be much better to know what happens when you first try to get a primate pregnant using a transplanted uterus before trying it in a human.”

However, he says that there seem to be no problems with the surgical procedures, if the transplant in monkeys was indeed a success – the results have yet to be published.

At present, the only option for a woman without a functioning uterus who wants her own child is IVF combined with surrogacy.