The Kyoto District Court held its first hearing on 3/6 in a lawsuit filed by a man against the legal entity operating a fertility hospital in Kyoto.
The man is seeking 10,5 million yen (73,000 USD) in compensation from the hospital. He alleges the facility failed to verify his consent, thereby enabling his ex-wife to use another man's sperm for conception while they were separated.
Court records show that in 1/2020, the couple signed a fertility treatment contract with the hospital, aiming for a second child. Following treatment, embryos were successfully created and cryopreserved.
In early 2022, the couple separated and began discussing divorce and asset division. During this period, the wife forged her husband's signature on a consent form, instructing the hospital to transfer frozen embryos into her uterus. This attempt was unsuccessful.
Later, she obtained a sperm sample from another man. She informed doctors it was from her husband and submitted another forged consent form. The hospital then proceeded with in vitro fertilization (IVF) according to its standard procedure.
The woman gave birth to her second child in 8/2023.
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Illustration: Asahi
Japanese media reports indicate the wife's actions—defying the law and forging documents to conceive—were an attempt to save her failing marriage. She eventually confessed the truth to her husband when she could no longer conceal it.
The husband filed a lawsuit against his ex-wife. In 4/2025, a court sentenced the woman to one and a half years in prison, with three years of probation, for document forgery.
On 26/3, he proceeded with the lawsuit against the hospital. He argued that doctors would have detected the forged documents and the non-paternal sperm sample if they had directly contacted him or confirmed via phone.
The hospital has rejected the compensation claim. The facility asserts that current legal regulations and professional guidelines do not mandate doctors to directly confirm with the husband at every treatment stage. Furthermore, the medical facility argued that it is not uncommon for a wife in an infertile couple to not inform her husband about a pregnancy, thus providing no grounds to suspect forged documents.
The Kyoto man and his wife have finalized their divorce. He maintains his paternal relationship on the birth registry for the child born in 2023 and fulfills child support obligations.
"The child is innocent and should not bear the consequences of adult actions," he stated.
Bao Nhien (According to Asahi)
