A woman undergoing in vitro fertilization treatment became pregnant at a Tokyo hospital this spring after concealing from doctors that her husband, who was believed to be infertile, was actually dead, according to hospital officials and sources close to the matter.

The incident at Hara Medical Clinic in Tokyo's Shibuya Ward has raised concerns over the ramifications for the child's biological father as infertility treatments were intended for married couples under the clinic's guidelines, and when donor sperm is used, the husband usually assumes legal parenthood.

File photo taken Feb. 8, 2023, shows frozen donor sperm at Hara Medical Clinic in Tokyo's Shibuya Ward. (Kyodo)

The Japan Society of Obstetrics and Gynecology also asks its members to limit treatments using donor sperm to married couples.

According to the sources, the woman deliberately concealed her husband's death from doctors, knowing it would render her ineligible to continue IVF with donor sperm, and attempted to conceive after discussions with her in-laws. She finally revealed her husband's death during a post-pregnancy consultation in June.

Japanese law does not cover cases in which the husband dies during IVF treatments. It is possible that, if identified, the sperm donor may be asked to legally accept recognition as the child's father.

The clinic, which reported the incident to the Japan Society of Obstetrics and Gynecology, has temporarily suspended IVF procedures using donor sperm and is considering whether or when it will resume them.

The clinic began recruiting sperm donors in February 2022, with around 150 people registering within a year. Since September last year, it has used non-anonymous donors for IVF treatments, where identifying information is disclosed when the child comes of age.

The clinic has since revised its guidelines to introduce preventive measures, including requiring the husband to provide verbal confirmation on the day of embryo transfer and participate in study sessions. The changes took effect this month.

"This incident has the potential to threaten the rights of the non-anonymous donor, as the patient's husband cannot become the legal parent of the child," the hospital said Sunday in a statement.

The hospital said it confirmed that the woman chose to conceal her husband's death as she "prioritized her strong desire to have a child."

"This medical treatment relies on trust and contract in Japan," where legal provisions for such a case do not exist, the hospital said, adding that the incident shakes such principles to their foundations.

The hospital said it plans to take legal recourse against the woman.

Rules for disclosing the details of donors in Japan as part of an individual's right to know their origins were included in a legislative framework for assisted reproductive technology drafted by a nonpartisan parliamentary group last year, but it has yet to be enacted.

Related coverage:

Preimplantation genetic testing leads to fewer miscarriages: study

FOCUS: Emotional support in short supply for Japan's would-be mothers

Japan to allow wider preimplantation genetic testing of eggs in IVF