A California hospital has been fined $25,000 for leaving a sponge inside a patient after a surgery, KPBS.com reported.

The sponge measured four inches by four inches.

The patient was admitted to San Diego’s Scripps Mercy Hospital in late 2007 for a hysterectomy. A year later, a routine imaging test showed a foreign object inside her, which an additional surgery failed to find. A third and final surgery removed a sponge the size of a cocktail napkin from her abdomen.

This is the third time that the hospital has been fined for safety lapses by the California Department of Public Health.

Dr. Davis Cracroft, medical director at Scripps Mercy Hospital, said a small percentage of human errors are inevitable.

"What we have to do is try and design our processes so that human errors are limited, and then mitigate the damage that occurs whenever possible," Cracroft said.

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