Katie Kropas was admitted to hospital after suffering from lower back pains, but she was in for a surprise when doctors told her what had been causing her symptoms.
It turns out she was about to give birth to a 10lb baby!
She told her local news station WCVB TV: “I came in with lower back pain on Tuesday morning.
"Later that night they put me in for an ultrasound, they took one look and rushed me off into labour."
The new mum- from Weymouth, Massachusetts- continued: “I found out that I was having a baby at 10.15pm and she was born at 11.06pm."
Katie had no idea she was pregnant and put her weight gain down to overindulging over the festive period.
"I started to feel like I had put on some weight but I had been [thinking] maybe that was just Christmas," she said.
A doctor at the hospital Katie gave birth in said: "Most people will say, 'how could you not have known?', but if you've never experienced it before they [pregnant women] don't really know what they should be experiencing or feeling."
Kate added: "They just say, 'you were carrying around 10 extra pounds and you didn't know it?' I don't know why I didn't know. I mean, I'm just excited and I appreciate everyone who is helping."