A University of Utah committee investigating reports that a Salt Lake City fertility clinic worker artificially inseminated a patient with his own sperm called the action "unacceptable" on Thursday, but said it could not determine whether the switch was intentional.

Practices at two now-closed Salt Lake-area clinics came into question last year when Pamela Branum, who was artificially inseminated at Reproductive Medical Technologies Inc, claimed genetic testing revealed that, instead of her husband, a lab technician had fathered their daughter in the early 1990s.

The technician, Tom Lippert, has since died.

The committee of three university physicians, tasked with reviewing the case and making recommendations to the institution, said in a report released on Thursday that it was unclear how the Branum switch occurred or whether it was accidental or done on purpose.

“Either explanation is unacceptable from the perspective of the committee and, presumably, the Branums and any other couples who might be similarly affected,” the report said.

Lippert, who had a criminal record, was hired without a background check in 1988 and worked part-time at both RMT and the Community Lab, the report said. He was also a registered sperm donor at the clinics and frequently supplied samples.

Lippert, considered a good worker by some but a problem employee by others, left the job in 1993 for unknown reasons and died six years later, the report said.

Sean Mulvihill, M.D., associate vice president for clinical affairs and CEO of the University of Utah Medical Group, apologized to the Branums for the swap on behalf of the University this week.

“No family should have to go through something like this, and we are deeply sorry for the stress and uncertainty this has caused their family,” Mulvihill said in a written statement.

In its report, the committee suggested that the institution continue to offer free paternity testing for one to two years to former clients concerned about their procedures.

The university said it had tested five people through an independent laboratory since January to try to determine whether Lippert had fathered any additional children.

The testing did not link Lippert to more offspring but did uncover a case where a child conceived by an anonymous sperm bank donor at one of the now-defunct clinics was not the donor selected by the family, the university said.

The university said it was investigating that case as well.

(Reporting by Laila Kearney; Editing by Dan Whitcomb and Gunna Dickson)