A sore back was bothering a runner from Duluth, Minnesota on Sunday evening, but what she didn't know was those pains were the beginnings of labour.
Trish Staine told the Associated Press she had trained for two hours in advance of a half-marathon and she thought she must have injured herself running. Not so.
Staine was pregnant, which she was shocked to discover upon arriving at the hospital in excruciating pain on Monday. Shortly afterward, she was holding a baby girl, according to the story.
Staine said she told doctors she couldn't possibly be pregnant, because the mother of two hadn't noticed any signs. She said her husband had also had a vasectomy.
Impossible or not, AP reported Staine gave birth to a baby at 3:25 p.m. on Monday and named her Mira, which is short for miracle.
Astonishing, but unknown pregnancies are common enough to sustain a reality television show on The Learning Channel, entitled I Didn't Know I Was Pregnant. The lack of symptoms could be related to powerful denial, according to an NBC report quoting a doctor that specialized in reproductive health.
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But even the strongest denial won't change the situation when it's time to greet your new baby.
In another recent tale of medical surprise, a Chinese man visited the hospital with stomach pain to discover he was actually a woman.