The time from transplant to the birth of a baby was the shortest worldwide, and experts say that could become the new standard.
In early 2023, after a 16-hour dual surgery, a young woman became Australia’s first uterus transplant recipient, later giving birth to a healthy baby boy via caesarean.
Not only was Kirsty Bryant’s uterus transplant – thanks to her mother’s donation – an Australian first, but it also became the shortest time between uterus transplant and birth internationally.
Following the success of their first uterus transplant, researchers at Sydney’s Royal Hospital for Women have revealed details of the procedure, pregnancy and birth in the Medical Journal of Australia and say the new standard for embryo transplant after uterus transplant could be two to three months.
Surgeon, paediatric and adolescent gynaecologist and fertility specialist Associate Professor Rebecca Deans led the surgery in collaboration with the Swedish team who performed the world’s first successful uterus transplant in 2014, led by Professor Mats Brännström.
Professor Deans said Ms Bryant had completed a full cycle of transplant, pregnancy, delivery and finally, hysterectomy.
“It’s been a bit of a journey, very intense, and I have really enjoyed it,” Professor Deans told The Medical Republic.
“It’s been wonderful as a proof of concept that it can be done, and everything seemed to really go well with that particular patient.
“She got pregnant straight away and had very few issues within pregnancy. She delivered at 37 weeks, everything went really well. So that’s really wonderful, because you’re always a bit anxious the first time you do something. So I was quite relieved that it all went so well.”
Professor Deans said the experience of having a uterus transplant was emotionally charged for the women taking part, who felt the pressure of being under the spotlight.
And as with any fertility treatment, there were multiple factors at play and no certainty of a successful pregnancy, she said.
“It’s challenging in that it’s huge surgery, and there’s a lot to the immunosuppression, and it’s a fertility treatment and with all fertility treatments, there’s highs and lows,” she said.
“We’re very lucky with Kirsty. She had a really smooth run. But with our third one, we haven’t been able to get her pregnant despite embryo transfer so we’re exploring why not. Is it to do with the embryos? What’s the exact reason?”
Professor Deans said the rate of uterus transplants was rising exponentially worldwide. According to the latest data from the Congress of the International Society of Uterus Transplantation released in October, there have been 146 uterus transplants internationally – up from 90 transplants a year ago – with more than 60 live births.
There have been four uterus transplants in Australia so far, including three at the Royal Hospital for Women – two of which have resulted in live births – and one at the Royal Prince Alfred Hospital, Professor Deans said.
The Royal Hospital for Women currently has another mother and daughter waiting to take part, and there are another 10 people waiting who don’t have donors, she said.
“So we’re hoping to start a deceased donor program,” Professor Deans said.
“If we can get that off the ground, then those people who don’t have a donor may have the opportunity to have a transplant.”
In Ms Bryant’s case, the researchers transferred a frozen blastocyst 101 days after the uterus transplant, six weeks after stopping the immunosuppressive mycophenolate mofetil (MMF).
That transfer resulted in a pregnancy 112 days after the uterus transplant – a shorter timeframe than the first pregnancy following the first Swedish transplant, which had been stable for a year before transfer.
Professor Deans said the time between uterus transplant and delivery was the shortest worldwide, and that decision was made to reduce the amount of time the patient was on immunosuppression and the potential side effects.
“There’s emerging evidence around optimising, because in the first studies, they would wait a full year before they started doing embryo transfers in case of rejection,” she said.
“But I think now that chance of rejection drops right off after about three months, and she had done really quite well at that time and it timed in with her return of period. She had her first period within a month of having her transplant, so everything started and went ahead smoothly.”
Professor Deans said the optimal time was probably three to four months – a topic that was debated at the recent conference.
“Some of the older immunosuppression protocols, you can’t get pregnant for a bit longer, and we’re using more low-risk ones, but you still want to be quite certain there’s no rejection,” she said.
The other issue was the risk of cytomegalovirus (CMV) infection – a risk that all organ transplant recipients face due to the effect of immunosuppressive drugs. That risk is especially high in the first six to 12 months after the transplant.
“If the mother contracts CMV, that’s really harmful to the foetus,” Professor Deans said.
Foetal CMV infection was a potentially serious complication that could cause developmental delay, intellectual disability and hearing and vision loss, she said.
“With our second one, we had to wait, because she was negative and the donor was positive. We had to wait to make sure she didn’t seroconvert before we started embryo transfers.”
But in Ms Bryant’s case, her CMV status was concordant with her mother’s, so the risk of CMV infection was much lower, Professor Deans said.
“And being mother to daughter, the chance of rejection is lower because they’re more immunologically similar,” she said.
“So there were a lot of things that worked in favour of being able to do it. You couldn’t necessarily say you could do that across the board, but I think that in her case, it worked well because of all the other factors.”
The researchers said reducing the duration of immunosuppression minimised the potential side‐effects such as renal impairment and malignancy.
“We decided that the earliest point for safe embryo transfer was after MMF washout, given its potentially fetotoxic effects,” they wrote in the MJA.
“This approach not only reduces the duration of immunosuppression for the recipient, it also reduces their waiting time for childbirth, fulfilling the primary reason for transplantation and undergoing the costs and risks of long-term immunosuppression.
“The time from UTx to delivery of a live term infant, within a single calendar year, is the shortest reported to date.
“The new standard for the first embryo transfer after UTx could be two to three months if no problems arise during this period.”
