The Argentine parents of a presumably stillborn baby found the girl breathing and alive when they visited the hospital morgue to say goodbye, according to media reports.

The infant, born three months premature on April 3 in Chaco, in northern Argentina, had been in a tiny coffin inside the refrigerated morgue for 12 hours, Sky News reports.

Analia Bouter, the mother, had insisted on seeing the infant because she had been sedated during the birth.

Attendants at Perrando de Resistencia Hospital had quickly taken the baby and issued a death certificate, saying she died of unknown causes, Bouter tells Todo Noticias television.

When she, and her husband, Fabian Veron, went to the morgue, they were shown a little casket on a stretcher.

"We looked for a bar to prize it open," Veron tells reporters. "The casket was nailed shut. I started to prize, took a deep breath and took the top off. My wife was the first one to look at the body and she uncovered it slowly."

Bouter says she thought she was hallucinating when she looked at the infant, heard a whimper and saw signs of life, the Associated Press reports.

Vernon says he started uncovering her face "and it was like she was just getting up, waking up."

They named the baby girl, who is reported to be in good condition, Luz Milagros, which means Miracle's Light. It is the couple's fifth child.

Provincial health officials have confirmed they are investigating the incident, the AP reports.