Singing or playing womb-like sounds in the neonatal intensive
care unit (NICU) may help slow the heart rate and improve sleep and eating
patterns of premature babies, a new study suggests.
Researchers found infants who had respiratory distress or
sepsis tended to do better while listening to their parents sing a lullaby or to
sounds mimicking a mother's heartbeat or fluid in the womb.
"We are learning from the literature and studies like this that
premature infants do not necessarily grow best tucked away in an incubator,"
said Joanne Loewy, head of the Louis Armstrong Center for Music and Medicine at
Beth Israel Medical Center in New York.
"Neurologic function can be enhanced with music; vital signs
can be enhanced through interactive sounds and music therapy," she
How the study was done
Her new study included 272 preemies being treated at 11 NICUs
that had music therapists.
At different times over two weeks, babies' parents sang to them
or therapists used one of two devices meant to simulate womb sounds for 10
Loewy and her colleagues compared preemies' vital signs during
those periods, as well as their eating and sleeping, to times when no sounds
They found the babies' heart rates dropped by one or two beats
per minute, on average, while they listened to the lullaby and heartbeat sounds
and just after they'd heard other womb-like sounds.
"The singing is extremely important because it represents
familiarity - the baby heard the mother and father's voice as early as 16
weeks," Loewy explained, "plus you have melody and rhythm in song."
Sucking rates speed up with the heartbeat sounds, in
particular, and there was a longer-term improvement in sleep patterns tied to
the womb-like fluid noises, the researchers reported.
Previous research into the soothing effects of music has found
mixed results among both babies and, for example, adults on ventilators in
There were no babies in the new study who were exposed only to
silence or quiet talking in the NICU, so the researchers can't say how these
preemies would have compared to a no-music group - only that they did better
while hearing music.
They said the sounds used in these NICUs can be replicated by
parents without the help of a music therapist, if one isn't
"The wonderful thing about these instruments is that the body
can take it over," Loewy said.
"We teach (parents) to hold the baby over the heart, to hold
them skin-to-skin, to make 'ahh' sounds to enhance that womb-like
Loewy said she and her colleagues especially encourage parents
to sing songs that are important to their family and culture, which can ease
their stress as well.