Friday 15 January 2010

British scientists move closer to womb transplant

Doctors say the first successful womb transplant may be performed within two years. Research on rabbits has shown that it is possible to transplant a uterus and provide a reliable blood supply so that the organ lasts long enough to enable a pregnancy.

The research, led by Richard Smith, a consultant gynaecological surgeon at Hammersmith Hospital in London, UK, and involving teams in New York and Budapest, was presented this week at the American Society for Reproductive Medicine (ASRM) annual conference in Atlanta. Surgery performed on rabbits at the Royal Veterinary College in London led to five rabbits receiving a successful womb transplant which included connecting major blood vessels and the aorta but they did not achieve pregnancy naturally. Two of the rabbits lived to ten months and post-mortem examinations proved the transplants to be a success.

It is reported that around 15,000 women of childbearing age are without a womb in the UK. Some of whom are born without one or have been required to have it removed because of cancer. For these women the only option at present to have children is either through adoption or surrogacy. It is estimated that up to 200 women use surrogate mothers every year. If womb transplants can in the future be successfully applied to humans then this would provide women with a viable alternative.

A human womb transplant has already been performed in Saudi Arabia on a 26 year old woman in 2000 but failed after the organ, taken from a live donor, was rejected and needed to be removed after three months. Smith thinks that the organ was rejected because of difficulties in ensuring adequate blood supply which resulted in a clot developing. The difficulty is that the womb needs to be functioning in the woman for the duration of a pregnancy, during which the recipient would be required to take immuno-suppressant drugs to reduce the risk of rejection. The womb would then be removed.

'I think there are certain technical issues to be ironed out but I think the crux of how to carry out a successful graft that's properly vascularised - I think we have cracked that one,' Smith told the conference. The technology still needs to be translated into a safe and effective method to be used in humans, and the team are yet to attempt to create a successful pregnancy in rabbits through IVF.

Tony Rutherford, chairman of the British Fertility Society, commented, 'I think there is a big difference between demonstrating effectiveness in a rabbit and being able to do this in a larger animal or a human...'. There are also ethical issues which will need to be addressed. Clare Lewis-Jones, from Infertility Network UK, said 'a great deal of thought and discussion' was needed before the research was applied to humans.

The team plans to use the technique on larger animals but the project is running out of money after research grants were rejected. To continue the research, a charity called the Uterine Transplant UK will be set up to help obtain the necessary funding of £250,000. The Times newspaper reports that surgeons in New York have already been given the go ahead to perform a human trial after demonstrating a uterus can be preserved long enough for surgery to be carried out.

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