Jodie Kenna, who came home from work with stomach cramps, decided to take a warm bath to ease the pain. But within minutes she delivered a healthy 7lb 5oz baby girl Elizabeth, reported the Daily Mail.
Doctors don't know how far was her pregnancy but the healthy weight of her baby indicated she was almost at full term.
Kenna and her partner Alan Whitehead said they were 'as pleased as punch' with the surprise arrival.
"But when it was happening I was terrified. I had no idea I was pregnant. It sounds mad but the midwives say it does happen.
"Alan was in shock when he came home to find me with a baby in my arms. He rushed from work to find Jodie in the bathroom surrounded by towels," stated the new mother.
"We are so happy with her. She is doing really well. And Evie is loving having a little sister," said Kenna, who also has a five-year-old daughter, Evie," she added.
"But when it was happening I was terrified. I had no idea I was pregnant.t sounds mad but the midwives say it does happen. Alan was in shock when he came home to find me with a baby in my arms. But he has got over it now and is really pleased," she added.
"I was really worried when I got there because the baby was blue. We just kept her warm and I told Jodie to get ready for the ambulance," said her mother, Elaine, who arrived soon afterward.