A virus infection Stephanie Connor acquired during pregnancy put her unborn daughter at significant risk for brain damage and lifelong hearing loss. "It was traumatic," said Connor, of LaBelle, Fl, after learning about her daughter's condition. "It was like mourning the loss of a child."

At age 1, baby Madeleine was completely deaf in her right ear and her hearing was severely lost in the left, said Connor. While a hearing aid helped to amplify some sounds for Madeleine, it would never fully repair the damage in her ear. But a simple experimental procedure that Connor enrolled in for Madeleine may have restored her hearing and reversed her condition.

In January 2012, Madeleine, 2, became the first child to undergo an experimental hearing loss treatment through an FDA-approved trial at Memorial Hermann-Texas Medical Center that infused stem cells from her own banked cord blood into her damaged inner ear.

For the first time, doctors are experimenting with cord blood stem cells to regenerate hearing in children who have suffered hearing loss. This yearlong study will follow 10 children, including Madeleine, ages 6 weeks to 18 months.