The wife of a man with the human immunodeficiency virus contracted the virus through artificial insemination at a university hospital in western Japan several years ago, a hematologist at a Tokyo hospital said Sunday.

While recent advancements in medical science have enabled HIV to be removed from sperm with a high degree of success, the university hospital is believed to have failed to completely remove the virus when conducting the operation in question.

The commonly used technique involves placing sperm in a centrifuge to separate the virus. Several procedures, including many highly sensitive checks at the genetic level, are then conducted to ensure that the sperm is HIV-free.

Hideji Hanabusa, hematologist at Ogikubo Hospital in Tokyo, said that the couple attempted artificial contraception six times at the university hospital after learning of the high degree of safety in using this removal method.

The wife never became pregnant, but was later found to have contracted HIV. Her physical condition has remained stable, the doctor said.

It is believed that the university hospital failed to thoroughly carry out the virus-removal process, Hanabusa said.

In order to protect the privacy of the couple, he withheld the name of the university hospital that conducted the artificial-reproductive treatment.

The doctor added there have been several other cases where sufficient steps have not been taken to prevent the virus from spreading. He said he would report these cases in his presentation at the upcoming annual meeting of the Japanese Society for AIDS Research, which starts Thursday in Nagoya.

Ten women with HIV-infected partners have become pregnant through in vitro fertilization since Tottori University Hospital succeeded in having a couple with an HIV infected husband get a virus-free child through artificial insemination in 2001. Of these, babies were born in three cases.