Spears has been admitted to hospital several times this year

The Los Angeles Times says workers at the UCLA medical centre looked at Spears' confidential files when she was admitted to the hospital in January.

Jeri Simpson, the hospital's head of human resources, confirmed to the AP news agency that several staff would be disciplined or fired over the incident.

"It's very frustrating and it's very disappointing," she said.

According to the Los Angeles Times, 13 staff - none of them doctors - will lose their jobs.

Another 12 will be disciplined for looking at Spears' computer records, it reported.

However, the hospital would not confirm these figures, nor would it say when the incident took place.

There is no evidence that the information was leaked or sold

This is not the first time the centre has had to reprimand employees for looking at Spears' records.

Several workers were fired for snooping after Spears gave birth to her first son, Sean Preston, in September 2005.

"We feel horrible that it happened again," Simpson said, adding that UCLA treats celebrities "all the time and you never hear about this".

"I don't know what it is about this particular person, I don't know what it is about her," she continued.

Spears was taken to UCLA by ambulance in the early hours of 31 January, and was reportedly held on a psychiatric ward.

Her father has since been given control of her assets and estate, and she has been allowed only limited contact with her two sons.