Uterine Transplants


I just knew it was going to happen; I could feel it in the air: a live and healthy baby delivered from a transplanted uterus.

It was the womb’s turn. After all, people have been trying to transplant stuff since anatomy began. Unfortunately, before the concepts of physiology, infection and immune rejection were appreciated, they all failed. Miserably.

There were exceptions, of course, such as the successful kidney transplant between identical twins in 1954 -where their immune systems were obviously identical as well- but until the ability to avoid the toxicity of anti-rejection drugs was improved, organ exchanges were limited to the desperate or the foolhardy.

A few solitary successes occurred late in the 19th century with skin grafting, but until good immune suppressors like cyclosporin (1970) were developed, most organs –that is to say, most patients– didn’t survive for more than two or three weeks.

And then it took off. Kidney transplants are now routine; heart transplants -while more dramatic because of the need for a healthy organ from an individual who is unfortunately unable to use it any more- no longer garner headlines like Dr. Christian Barnard’s first success in 1967.

And the list of organs being transplanted is beginning to read like an anatomy textbook. Everything from pancreas to lung, combo packs like heart/lung, and even an entire face in 2013. If you can name it, somebody somewhere is trying to transplant it. So it was surprising that the poor uterus was left sitting in the shadows for so long.

In fairness, though, it had been attempted several times before in various medical centers, with little success –ie  ability to do what the uterus was designed to do: incubate and deliver a  live, healthy baby. Not until the 2013 transplant in Gothenburg Sweden, with Dr. Brannstrom’s surgical team was a live baby born from a uterus a year after it was installed. Everything seemed to work –the recipient began to menstruate regularly- so one year after the transplant, having cryopreserved an embryo beforehand, it was placed into the uterus and followed closely as it developed.

http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)61728-1/abstract

The baby was born prematurely (at 31 weeks and 5 days, rather than at the average 40 weeks) because, although blood supply to the uterus was apparently normal, the patient developed pre-eclampsia (pregnancy-related high blood pressure) and there were some problems with the baby’s heart rate that apparently mandated delivery.

Were these complications the result of the transplanted organ (the donor was an unrelated 61 year old post-menopausal woman), the immosuppressants (she was on a triple therapy consisting of tacrolimus, azathioprine, and corticosteroids), or just bad luck? And would such a transplant be able to function normally –like a transplanted heart, say- and contract efficiently enough to enable labour and vaginal delivery? Or would a caesarian section be required in all cases? It’s probably too early to say.

So congratulations to the parents and the transplant team. Fortunately, the need for uterine transplantation is uncommon, and adoption, or even surrogacy remain as other less drastic options. But it seems to me there are issues that, despite the success, have yet to be adequately addressed.

Ethical issues, for one thing. Unlike, say heart or kidney transplants where death may ensue if transplantation is not available in a timely fashion, the uterus is not essential for the continuation of life. And the procedure entails sophisticated, difficult and risky surgery that is frought with possible life-theatening complications in and of itself –including, of course, rejection of the organ despite the immunosuppressants. The surgery, by the way, is far more arduous and byzantine than the routine hysterectomies that are over-performed around the globe –extra tissue has to be obtained along with additional dissection to be able to reconnect the arteries and veins efficiently. So both donor and recipient are at increased risks…

But what troubles me the most I suppose, are the possible long term effects of the immunosuppressants on the developing foetus growing inside the transplanted organ. Azathioprine, for example. It interferes with DNA synthesis, and inhibits the proliferation of quickly growing cells… That seems a lot like what needs to happen in a rapidly growing foetus, doesn’t it? Azathioprine is a pregnancy Category D substance: to be used in life-threatening emergencies only when no safer drug is available. And there is positive evidence of human foetal risk. Even tacrolimus doesn’t have a lot of available human studies in pregnancy.

No doubt safer and more predictable immunosuppressants will be found, but for now I remain concerned that we may be trading something away. Just because we can do something, doesn’t mean we should. Unlike other organ transplants where the risk is assumed by the recipient alone, uterine transplants for reproduction share the risks with a rapidly developing and vulnerable foetus which might not manifest any problems until years in the future.

I realize I may be dismissed as a male Cassandra, a person who cannot see dawn through the warp and weft of the cobwebs of his past, but sometimes we have to stand back for a moment. Sit down and think things through. Decide whether we’ve gained more than we’ve lost, and whether it will be too late to change our minds if and when some damage is revealed.

In this case, one would be well to think of Mabeth’s dilemma:

I have no spur to prick the sides of my intent, but only Vaulting ambition, which o’erleaps itself

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