CLEVELAND, Ohio — Six doctors swarmed around the body of the dead
organ donor and quickly started to operate. The kidneys came out first.
Then the team began another delicate dissection, to remove an organ that
is rarely, if ever, taken from a donor. Ninety minutes later they had
it, resting in the palm of a surgeon’s hand: the uterus.
The
surgery was a practice run. In the next few months, surgeons at the
Cleveland Clinic in Ohio expect to become the first in the US to
transplant a uterus.
The recipients will be women who were either born without a uterus, had it removed or have uterine damage.
The
transplants will be temporary: each uterus will be removed after the
recipient has had one or two babies, so she can stop taking transplant
antirejection drugs.
Uterine transplantation is a new frontier,
pairing specialists from two fields known for innovation and for pushing
limits, medically and ethically: reproductive medicine and transplant
surgery. If the procedure works, many women could benefit: an estimated
50,000 women in the US do not have a uterus. But there are potential
dangers.
The healthy recipients will risk surgery and
antirejection drugs for a transplant that they do not need to save their
lives. Their pregnancies will be considered high risk, with the
foetuses exposed to antirejection drugs and developing inside a womb
taken from a dead woman.
Eight women from throughout the country have begun the screening process at the clinic, hoping to be selected.
One, a 26-year-old with two adopted children, said she still craved a chance to become pregnant and give birth.
She
was 16 when medical tests, performed because she had not begun
menstruating, found that she had ovaries but no uterus — a syndrome that
affects about one in 4,500 newborn girls.
DR ANDREAS G Tzakis, the driving force behind the project, said:
"There are women who won’t adopt or have surrogates, for reasons that
are personal, cultural or religious." Tzakis is the director of
solid-organ transplant surgery at a Cleveland Clinic hospital in Weston,
Florida. "These women know exactly what this is about. They’re informed
of the risks and benefits. They have a lot of time to think about it,
and think about it again. Our job is to make it as safe and successful
as possible."
The hospital plans to perform the procedure 10 times
as an experiment, and then decide whether to continue. Tzakis said he
hoped to eventually make the operation readily available in the US.
Sweden
is the only country to have uterine transplants completed successfully —
all at the University of Gothenburg, with a uterus from a live donor.
Nine women have had them, and four have given birth, the first in
September last year. Another is due in January. Their babies were born
healthy, although premature. Two transplants failed and had to be
removed, one because of a blood clot and the other because of infection.
Two
earlier attempts — in Saudi Arabia and Turkey — failed. Other hospitals
in the US and Britain are also preparing to try the surgery, but are
not as close as the team in Cleveland is.
Tzakis said the
antirejection drugs were safe, noting that thousands of women with donor
kidneys or livers, who must continue taking antirejection drugs during
pregnancy, had given birth to healthy babies. Those women are more
likely than others to have pre-eclampsia, a complication of pregnancy
involving high blood pressure, and their babies tend to be smaller. But
it is not known whether those problems are caused by the drugs, or by
the underlying illnesses that led to the transplants. Because the women
receiving uterine transplants would be healthy, Tzakis said, he was
optimistic that complication rates would be very low.
A medical
ethicist not connected with the research, Jeffrey Kahn of Johns Hopkins
University, said the procedure did not set off any alarms with him.
"We’re
doing lots of things to help people have babies in ways that were never
done before," he said. "It falls into that spectrum."
Dr Eric
Kodish, director of the clinic’s ethics centre, said that when organ
transplantation started more than 50 years ago, the goal was purely to
save lives, but has broadened to include improving quality of life,
with, for example, face and hand transplants.
Tzakis, 65, said he
had performed 4,000-5,000 transplants of kidneys, livers and other
abdominal organs. To prepare for the uterine surgery, he spent time with
the Swedish team, practising in miniature pigs and baboons, and
observing all nine of the human transplants in the operating room.
He
described transplantation as ethically superior to surrogacy. "You
create a class of people who rent their uterus, rent their body, for
reproduction," he said of surrogacy.
"It has some gravity. It possibly exploits poor women."
The
Swedish team used live donors, and showed that a uterus from a woman
past menopause, transplanted into a young recipient, can still carry a
pregnancy. In five cases, the donor was the recipient’s mother, which
raised the dizzying possibility of a woman giving birth from the same
womb that produced her.
The Cleveland doctors will use dead
donors, to avoid putting healthy women at risk. For a live donor, the
operation is far more complicated than a standard hysterectomy and takes
much longer, seven to 11 hours, Tzakis said.
"You have to work near vital organs."
The
surgeons have to remove part of the donor’s vagina and other tissue
needed to attach the uterus to the recipient. And they must tease away
tiny blood vessels without harming the donor.
The uterine vessels
are wound around the ureters, which carry urine from the kidneys to the
bladder. "They’re like worms wrapped around a tube," Tzakis said. "It’s
very tedious to separate them."
With dead donors, there is no need
to worry about injuries. The organ can be removed faster, and can
survive outside the body for at least six to eight hours if kept cold.
For
a prospective recipient of a uterus, the process is long and
complicated. To be eligible, candidates must be in a stable
relationship, because they will need help and support. They must also
have ovaries. The initial phase includes screening for psychological
disorders or relationship problems that could interfere with a
candidate’s ability to cope with a transplant and be part of a study.
Candidates are also interviewed to make sure they are not being
pressured to have the transplant. Doctors use similar criteria for
people receiving other types of organ transplants because the process is
arduous, and patients with a strong social support system seem to fare
better.
FINANCES matter, too, because during parts of the study, recipients
will have to live in Cleveland, and those from out of town will have to
pay for their food and lodging.
Because the fallopian tubes will not be connected to the transplanted uterus, a natural pregnancy will be impossible.
Instead
the recipients will go through in-vitro fertilisation. Before the
transplant, the woman will be given hormones to stimulate her ovaries to
produce multiple eggs. Ten will be needed, so she may have to go
through more than one cycle of hormone treatment. Doctors will collect
the eggs, fertilise them with her partner’s sperm and freeze them.
Once
there are 10 embryos in the freezer, the woman will be put on the
waiting list for a transplant. When a donor with matching blood-and
tissue-type becomes available, the transplant will take place.
The
transplant surgery is expected to take about five hours. It requires
connecting an artery and a vein on either side of the uterus to the
recipient’s blood vessels. The organ will have part of the donor’s
vagina attached, and that will be stitched to the recipient’s vagina.
Supporting tissue attached to the uterus will be sewn into the pelvis to
stabilise the transplant. No nerves have to be connected.
The
woman will wait one year to heal from the surgery and adjust the doses
of antirejection drugs before trying to fall pregnant. Then doctors will
implant one embryo at a time in the uterus, until she becomes pregnant.
The baby will be delivered by Caesarean section before the due date, to
protect the transplanted uterus from the strain of labour.
After
giving birth, the mother can either keep the uterus so she can try to
have one more baby (two is the limit, for safety reasons), or have it
removed so she can stop taking the antirejection drugs. If she does not
want surgery to have it removed, doctors said it may be possible to quit
the drugs and let the immune system reject the uterus, which should
then gradually wither away.
One of the surgeons working with
Tzakis will be Dr Tommaso Falcone, the Cleveland Clinic’s chairman of
obstetrics and gynaecology. Falcone said he first heard of uterus
transplants about 10 years ago, in early research described at medical
conferences.
Initially, he was sceptical, but a trip to Sweden in
2013 changed his mind. He watched the surgery and spoke to several
couples who wanted it.
"I almost cross-examined them. I was thinking there’s got to be something wrong with these people."
But he had come to understand how much pregnancy meant to them.
"It’s
a legitimate request. I got on the plane and knew I would be at the
forefront of trying to make this programme work at the Cleveland
Clinic."
Dr Alan Lichtin, chairman of the clinic’s 15-member
ethics board that evaluates research projects, said the medical team and
the board went back and forth many times, and it took about a year to
produce a plan that the board could approve.
The final vote was overwhelmingly in favour of the project.
NYTimes
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