"A lot of times families become afraid of interacting with their children because they are so sick and so frail, and music provides them something that they can still do," Klinger said, who works full time as a music therapist but her services are provided for free.
Music therapists say live performances in hospitals are better than recorded music because patients can feel the music vibrations and also benefit from seeing the musicians.
More than two dozen U.S. hospitals offer music therapy in their newborn intensive care units and its popularity is growing, said Joanne Loewy, a music therapist who directs a music and medicine program at Beth Israel Medical Center in New York.
Preemies' music therapy was even featured on a recent episode of the hit TV show "American Idol," when show finalist Kree Harrison watched a therapist working with a tiny baby at Children's Hospital Los Angeles.
"Music is such a huge part of our lives and to do something like this, make it a sort of healing process, is a cool thing," Harrison said on the April 25 episode.
Dr. Natalia Henner, a newborn specialist at Lurie hospital, said studies in nursing journals show music therapy for preemies "does help with promoting growth. And there's some good literature ... saying that the time to discharge is a little bit shorter in babies who've been exposed to more music therapy."
She said it "definitely facilitates bonding" between parents of preemies and other babies too sick to go home.
Loewy led a study published last month in the journal Pediatrics, involving 11 U.S. hospitals. Therapists in the study played special small drums to mimic womb sounds and timed the rhythm to match the infants' heartbeats. The music appeared to slow the infants' heartbeats, calm their breathing, and improve sucking and sleeping, Loewy said.