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5 Unbelievable Deliveries

World's Youngest Premature Infant Survives and Thrives
Shown here at nearly three months of age, fraternal twins Rumaisa (right) and Hiba pose with their parents.
Shown here at nearly three months of age, fraternal twins Rumaisa (right) and Hiba pose with their parents.
Oscar Izquierdo/Loyola University Medical Center/Getty Images

To appreciate Rumaisa Rahman's dimensions at birth, imagine holding a small sub sandwich from a popular fast-food chain. Delivered by cesarean section on Sept. 19, 2004, Rumaisa weighed 8.6 ounces (245 grams) and measured 9.5 inches (24 centimeters). She remains the smallest known surviving premature infant. Her twin, Hiba, weighed 1.25 pounds (566 grams), robust by comparison. The average American newborn weighs 7.5 pounds (3.4 kilograms) and measures 20 inches (50 centimeters) [source: Meyerhoff].

The girls were delivered at 26 weeks' gestation after their mother, Mahajabeen Shaik, developed dangerously high blood pressure, a pregnancy-related condition called preeclampsia. Their stage of development put them on the cusp of survival. Had they been born three weeks earlier, they would have had only a 20 percent chance of living, and probably with serious physical disabilities. Infants at 28 weeks and later stand a 90 percent chance of living without major impairment [source: Rochman].

Tipping the odds in the twins' favor: Premature girls fare better than boys, and their doctor had delivered the previous record-holding preemie in the same hospital, Loyola University Medical Center in Chicago, 15 years before. Shaik had been given steroids to spur the twins' brain and lung development. After delivery, they were attached to respirators with breathing tubes the size of spaghetti strands.

As of 2011, Rumaisa was in first grade, following an Individualized Education Plan (IEP). She was lagging slightly in fine motor skills in school but on par for language skills [sources: BBC World Service; CBS News; USA Today]. However, successful outcomes like hers are the rare exception.

Next: One perilous birth means life for thousands of children -- and adults.