Keio University Hospital in Tokyo has stopped taking appointments for a certain type of fertility treatment due to a fall in the number of anonymous sperm donors.
According to the hospital, fewer donors were willing to participate once they were made aware of the spreading global recognition of children's rights to know their biological parents.
Artificial insemination is used by couples when the man is infertile.
Mamoru Tanaka, an obstetrics professor at the university who oversees the treatment, noted that if Japan recognizes donor-conceived children's right to know their biological origins, it could lead to cases in which they effectively have two fathers.
"It is crucial to establish through legislation a safe and comfortable donor system," he said.
The hospital has been offering the treatment since 1948 and conducted around 1,500 procedures per year. It used to take appointments as early as a year in advance but stopped doing so in August. It will discuss the procedure's future in a meeting with outside experts in October.