A 26-year old woman gave birth in the bathroom of a sports bar and dumped her newborn baby in the toilet before returning to her friends to watch a wrestling match on TV, American prosecutors have claimed.

Amanda Hein was with three friends at Starters Pub near Bethlehem, Pennsylvania, when she went to the bathroom for 40 minutes. She returned with blood on her clothes.

Bar staff found the baby's bloody body in a toilet cistern and police were called.

They found blood where she had been sitting with her friends and pulled her in for questioining. She confessed that she had given birth to a live baby boy and that she had killed him, wrapped the body in a plastic bag and had hidden it in the toilet.

Bar owner David Rank said: "My biggest concern is for my employees, the mother, the baby."

According to Lehigh Valley Express-Times, the autopsy stated that Hein had given birth to a healthy, full-term baby boy and the child suffocated to death.

The suspect said that she realised she was pregnant in May but did not tell anyone. None of her friends who were with her that night knew that she was even carrying a child, prosecutors said.

"I cannot get inside this lady's head," District Attorney John Morganelli said.

If convicted, Hein could face the death penalty.