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(CNN) Fifty-one minutes is all the time Katie Kropas had to prepare for what most expectant mothers spend nine months planning for: motherhood.

"I found out at 10:15 and I had her at 11:06," Kropas told CNN affiliate WBZ

The Massachusetts woman said she woke up Tuesday morning with lower back pain so severe, she was rushed to a hospital in Weymouth, south of Boston.

"They told me that I had a full-term baby, ready to come now," she said.

Less than a hour later, Kropas gave birth to her 10 pound, 2 ounce daughter Ellie.

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