A Swedish doctor says four women who
received transplanted wombs have had embryos transferred into them in an
attempt to get pregnant.
He would not say whether any of
the women are pregnant.
Since 2012, nine women have received wombs
donated by their mothers or other close relatives in an experimental procedure
designed to test whether it's possible to transfer a uterus so a woman can give
birth to her own biological child. The women had in-vitro fertilisation before
the transplants, using their own eggs to make embryos.
Read: In-vitro fertilisation increases tumour risk
"We have already begun transferring
embryos into four of the women and plan to make attempts with the others when
they are ready," said Dr Mats Brannstrom, a professor of obstetrics and
gynaecology at the University of Goteburg, who is leading the research.
Brannstrom predicted that three or four of
the seven women might successfully give birth.
"One or two more will perhaps get
pregnant and miscarry and one or two won't be able to get pregnant," he
Two previous attempts
There have been two previous attempts to
transplant a womb – in Turkey and Saudi Arabia – but both failed to produce
babies. Doctors in Britain and Hungary are also planning similar operations,
but using wombs from dead donors.
Brannstrom said any woman in the study who
does get pregnant will be on a low dose of drugs to keep from rejecting the
transplanted womb and will be monitored as a high-risk pregnancy.The transplants are intended to benefit
women unable to have children because they lost a uterus to cancer or were born
Read: Babies learn language in the womb
Some doctors said women who got pregnant
with a new uterus would have to be watched carefully for how the womb
progresses throughout pregnancy.
"There are questions about how the
physiological changes in the uterus will affect the mother and whether the
transplanted uterus will be conducive to a growing baby," said Dr. Charles
Kingsland, a spokesman for Britain's Royal College of Obstetricians and
'Mild rejection episodes'
In a study published last week, Brannstrom
and colleagues described the procedures used to transplant the nine wombs and
said there were "mild rejection episodes" in four patients. Of the
nine who got transplanted wombs, two had to have them removed because of
Brannstrom said the transplanted wombs
would be removed after a maximum of two pregnancies.
Read: Risks of exposure to smoking in womb
Other experts called it a promising step
but said it would be crucial that babies get enough nutrients from the mother's
"We really don't know if the blood
flow to the uterus will increase and adapt in the same way," as in a
regular pregnancy, said Dr Yacoub Khalaf, director of the Assisted Conception
unit at Guy's and St. Thomas' hospital in London.
"It is a good sign they have done the
(embryo) transfers," Khalaf said. "But a live birth will be the best
validation that this works."
Womb transplant, hope for women
Nine Swedish women receive transplanted wombs
Womb transplants on the cards