ABC News: A strange tale of oral sex, a knife fight and the most unlikely of pregnancies recently brought to light by the blogosphere has doctors touting the triumphant persistence of sperm.

In 1988, a 15-year-old girl living in the small southern African nation of Lesotho came to local doctors with all the symptoms of a woman in labor. But the doctors were quickly puzzled because, upon examination, she didn't have a vagina.

"Inspection of the vulva showed no vagina, only a shallow skin dimple," so doctors delivered a healthy baby boy via Caesarean, the authors wrote in a case report published in the British Journal of Obstetrics and Gynaecology.

Her birth defect -- called Mullerian agenesis or Mayer-Rokitansky-Küster-Hauser syndrome -- didn't necessarily surprise doctors, but her pregnancy did. Even the 15-year-old girl could not believe she was pregnant.

Yet by looking at her records the hospital staff realized the young woman was in the hospital 278 days earlier with a knife wound to her stomach. The average pregnancy lasts 280 days. After interviews, they gathered that "Just before she was stabbed in the abdomen she had practiced fellatio with her new boyfriend and was caught in the act by her former lover. The fight with knives ensued."

The girl arrived at the hospital with an empty stomach -- and therefore with little stomach acid around -- and doctors found two holes from a stab wound that opened her stomach up to her abdominal cavity. The case report said doctors washed her stomach out with a salt solution and stitched her up.

"A plausible explanation for this pregnancy is that spermatozoa gained access to the reproductive organs via the injured gastrointestinal tract," the authors wrote.

Infertility experts note the story, which resurfaced on a Discovery magazine blog, is not only a testament to Murphy's Law but one to arguably nature's most impressive swimmers: sperm.

For more, go to ABCNews.com

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