A woman in Brazil has had surgery to remove a catfish from her stomach.

The fish embedded itself in her belly while she was swimming in the São Paulo beach resort of Itanhaém, Metro reported.

The woman was taken to hospital, where the fish and its spines were extracted from her skin in surgery, a local ambulance worker wrote on Facebook.

The catfish embedded its spikes in the woman's stomach (Marcelo Araújo Tamada/ Facebook)

“We were alerted to an incident where an object had penetrated a swimmer’s stomach and when we got there, discovered it was a fish,” wrote Marcelo Araujo Tamada.

“She was in a lot of pain. We didn’t remove the spine because only a doctor can do this. We took her to hospital so she could have microsurgery.

“Generally we deal with people who have stood on fish or have cut a finger touching one, but I’ve never seen a catfish stuck to someone’s stomach. It was definitely a first.”

Footage emerged in 2015 of a catfish becoming lodged in a woman's thigh after her friend slapped her with the animal.