Uterus transplantation is a sophisticated medical procedure that involves implanting a healthy uterus from a donor into a recipient. This advanced surgical intervention offers a pathway to pregnancy for individuals unable to carry a child due to uterine issues, addressing a specific form of infertility.
Understanding Uterus Transplants
Uterus transplantation addresses Uterine Factor Infertility (UFI), a condition where a person cannot become pregnant because their uterus is either absent or not functioning correctly. UFI can be congenital, meaning an individual is born without a functional uterus, often due to conditions like Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, which affects about one in 4,500 females. Alternatively, UFI can be acquired later in life due to various factors, such as surgical removal of the uterus (hysterectomy) for benign or cancerous conditions, or damage from infections, fibroids, or scarring.
This procedure is specifically intended for women of childbearing age, typically between 18 and 45, who have functioning ovaries but cannot carry a pregnancy to term due to uterine issues. Before the advent of uterus transplantation, options for these individuals to have biological children were limited to surrogacy or adoption. The first successful live birth following a uterus transplant occurred in Sweden in 2014, demonstrating the procedure’s feasibility and paving the way for its development globally.
The Transplant Procedure
Uteruses can be sourced from either living or deceased donors. Living donors are typically women between 30 and 50 years old who have completed their own childbearing and are in good health. This type of donation involves a complex hysterectomy, which can take up to 10 hours, as surgeons must meticulously preserve the uterus and its vascular connections without damaging surrounding tissues. Deceased donors, often brain-dead individuals, also provide viable grafts, and their use eliminates surgical risks for a living person.
The recipient surgery involves carefully placing the donated uterus into the recipient’s pelvis. Surgeons connect the major blood vessels of the transplanted uterus to the recipient’s blood supply, ensuring proper blood flow. The uterus is also connected to the recipient’s vagina. Notably, the fallopian tubes are not typically reconnected, meaning natural conception is not possible after the transplant.
The recipient typically begins taking immunosuppressive medications before surgery. The transplant surgery itself can take between six and eight hours.
Pregnancy and Delivery After Transplant
After a successful uterus transplant and a recovery period, typically several months, natural conception is not possible because the fallopian tubes are not reconnected. Therefore, In Vitro Fertilization (IVF) is necessary to achieve pregnancy. Before the transplant surgery, eggs are retrieved from the recipient’s ovaries, fertilized with sperm, and the resulting embryos are frozen for later use.
Once the transplanted uterus has healed and is deemed ready, one of these pre-created embryos is thawed and transferred directly into the uterus. Pregnancy with a transplanted uterus is considered high-risk and requires close medical monitoring by a team of specialists, including maternal-fetal medicine providers. The recipient must continue taking immunosuppressive medications throughout the pregnancy to prevent organ rejection, and regular checks, including cervical biopsies, are performed to monitor the uterus.
Delivery after a uterus transplant is almost always performed via a planned Cesarean section (C-section) to minimize stress on the transplanted organ and prevent complications. Babies born to uterus transplant recipients tend to be delivered slightly early, often around 35 to 37 weeks of gestation. While premature, these infants have generally shown no congenital malformations or developmental delays.
Post-Transplant Life and Outcomes
Ongoing medical management is required after a uterus transplant to ensure the health of both the recipient and the transplanted organ. A primary aspect of post-transplant care is the continued use of immunosuppressive medications. These drugs are necessary to prevent the recipient’s immune system from rejecting the transplanted uterus, though they carry considerations such as an increased risk of infection.
Uterus transplantation has shown promising success rates in terms of live births. Recent studies indicate that a significant percentage of recipients who undergo a successful transplant achieve at least one live birth. For instance, one study found that 14 out of 20 participants (70%) had a successful transplant, with all 14 giving birth to at least one healthy infant. Another report noted that among recipients with a viable graft one year after transplant, 83% achieved a live birth. As of 2023, over 100 uterus transplants have been performed globally, resulting in approximately 50 live births worldwide.
The transplanted uterus is not intended to remain in the recipient indefinitely. It is typically removed through a hysterectomy once the recipient has achieved their desired family size, usually after one or two pregnancies. This removal allows the recipient to discontinue immunosuppressive medications, thereby avoiding their long-term side effects. The uterus may also be removed if complications arise, such as graft failure or repeated unsuccessful embryo transfers. The process from transplant to successful birth can span two to five years for many individuals.