The Japanese Association of Medical Sciences said Wednesday it has conditionally approved womb transplants to be performed in Japan on a clinical trial basis, providing hope to women in the country struggling with infertility.

In a report compiled by the association's review panel, it said such transplants will be limited to a small number of cases. The procedure involves transplanting the uterus of a living donor to a woman who lacks a uterus so that she can give birth.

Masamitsu Iino (R), chairman of the Japanese Association of Medical Sciences' review panel on womb transplants, and Morito Monden, the association's president, hold a press conference in Tokyo on July 14, 2021. (Kyodo)

Current organ transplant laws in Japan do not permit uterine transplants from deceased donors, so a donor is likely to be the mother or another family member of the patient.

A team at Keio University now plans to seek permission from its internal ethics committee to carry out what would be Japan's first clinical trial of a uterine transplant.

Under the procedure, egg retrieval will be performed on the patient in advance, fertilized in-vitro, and then frozen for storage. The embryos will be later implanted inside the transplanted uterus, with the baby delivered via cesarean section.

There are believed to be around 60,000 women in their 20s or 30s in Japan who are either born with Mayer-Rokitansky-Kuester-Hauser syndrome, a condition that causes the uterus to be underdeveloped or absent, or who have lost their uterus as the result of cancer treatment and other causes.

While it is hoped uterine transplants will provide these women with a new option to have children, there are still many issues left to be resolved, including whether it is appropriate to perform a hysterectomy on a healthy woman, and the unknown side effects of immunosuppressive drugs, administered to suppress organ rejection, on a fetus.

The association's report stipulates that a womb transplant can be performed in Japan on condition that all concerned parties including the donor and patient have been fully briefed on the process and understand the risks involved.

It also urges medical bodies to ensure a support system for diagnosis and treatment of those with MRKH syndrome, and recommends revising an ordinance of the law to prepare for allowing transplants from deceased donors in the future.

In 2014, doctors in Sweden became the first to successfully deliver a baby from a transplanted human uterus.

Since then, the procedure has been performed in 16 countries, including the United States, resulting in 40 successful births as of March 2021, according to the review panel. In most cases, the donor is the patient's mother.

Keio University submitted its clinical trial proposal to entities including the Japanese Society of Obstetrics and Gynecology in 2018.

The Japanese Association of Medical Sciences established a review panel in 2019 to evaluate the proposal and to discuss the ethical concerns.

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