A uterus transplant is a medical procedure that involves surgically implanting a healthy uterus into an individual who lacks a functional uterus or has one that cannot carry a pregnancy. This treatment offers a pathway to biological motherhood for those with uterine factor infertility. Its primary goal is to enable a woman to experience pregnancy and achieve a live birth, addressing a previously irreversible form of infertility.
Understanding Uterus Transplants
Uterus transplantation addresses uterine factor infertility (UFI). This condition means a person cannot become pregnant or carry a pregnancy to term because their uterus is absent or non-functional. UFI affects approximately 3-5% of reproductive-aged women globally.
Candidates for a uterus transplant include women born without a uterus, a condition known as Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, which affects about 1 in 4,500 females. Other potential recipients are individuals who have had their uterus surgically removed due to medical reasons, such as a hysterectomy for severe endometriosis, uterine fibroids, cancer, or childbirth complications. Women with a uterus that is present but non-functional due to severe scarring, malformations, or other abnormalities may also be considered, as these issues can prevent proper embryo implantation or fetal growth.
The transplanted uterus can come from either a deceased or a living donor. Living donors undergo a complex surgical procedure to retrieve the uterus. Both donor types require extensive medical evaluation to ensure suitability and minimize risks.
The Transplant Journey
The journey for a uterus transplant recipient begins with a comprehensive pre-transplant evaluation. For individuals pursuing pregnancy, this stage also involves in vitro fertilization (IVF) to create embryos using their own eggs and a partner’s or donor’s sperm. These embryos are then frozen, as natural conception is not possible after the transplant since the fallopian tubes are not typically reconnected.
The surgical phase involves two major procedures if a living donor is used: the donor hysterectomy and the recipient transplant surgery. The donor surgery is a complex procedure to remove the uterus, including its blood vessels, fallopian tubes, cervix, and a portion of the vaginal cuff. This can take several hours and carries inherent surgical risks for the donor.
Following donor surgery, the recipient undergoes a transplant operation where the donor uterus is attached, connecting its blood vessels to the recipient’s iliac vessels. After the transplant, the recipient receives immediate post-operative care, including immunosuppression therapy to prevent the body from rejecting the new organ. This medication regimen is based on protocols used in other solid organ transplants, like kidney transplants, and continues throughout the life of the transplanted uterus.
Once the transplanted uterus has healed and stabilized, after a waiting period of about 3 to 12 months, frozen embryos are transferred into the uterus. Many programs now aim for a shorter waiting period, often around six months, to reduce the recipient’s long-term exposure to immunosuppressive therapy. If the embryo successfully implants, the recipient becomes pregnant, with the pregnancy closely monitored by high-risk obstetricians. Deliveries are performed via Cesarean section to protect the transplanted uterus and avoid the stresses of vaginal birth.
Outcomes and Important Considerations
Uterus transplantation has shown successful outcomes, with a growing number of live births worldwide. Recent studies indicate high live birth rates among women who achieve successful graft survival. One study showed a 70% live birth rate among participants with successful grafts. As of May 2024, 48 uterus transplants and 33 live births have been reported in the United States. Globally, over 100 uterus transplants have been performed, resulting in more than 70 live births.
The transplanted uterus is not intended to be a permanent organ within the recipient’s body. It is removed after one or two successful pregnancies. This temporary nature allows the recipient to discontinue immunosuppressive medications once their family-building goals are met, mitigating the long-term risks associated with these drugs.
As with any organ transplant, there are medical considerations and potential complications. The immune system’s natural response is to reject foreign tissue, necessitating continuous immunosuppression. Side effects of immunosuppressive medications can include increased susceptibility to infections, potential kidney function issues, and an elevated risk of certain cancers.
Pregnancies in a transplanted uterus are considered high-risk. Potential complications for the mother can include gestational hypertension, preeclampsia, and preterm delivery. Babies born from uterus transplant recipients tend to be born earlier, often around 35 weeks of gestation, which may necessitate a stay in a neonatal intensive care unit. While adverse events are common, studies have reported no congenital malformations or developmental delays in the infants born from these procedures.