Hearing recordings of their mothers' voices and heartbeats helps premature babies in incubators mature faster, according to a new study.

By Hollee Actman Becker
February 16, 2016
Credit: Beth Swanson/Shutterstock

Here's something I wish I knew back when my daughter was born at just 32 weeks: Recordings of mothers' voices and heartbeats may help premature babies mature faster. According to neuroscientist Amir Lahav, ScD, assistant professor of pediatrics at Harvard Medical School, babies who are placed in incubators in intensive care units for long stretches of time often don't hear anything but the sounds of machines beeping and the white noise of fans whirring—and those sounds might actually be delaying their growth.

In order to find out, Dr. Lahav decided to conduct a study. Several days after the birth of their premature babies, he asked 12 mothers to record themselves singing, reading, and talking. Dr. Lahav and colleagues then added audio of the mothers' heartbeats to the recordings. Then those sounds, along with recordings of the mothers' heartbeats, were piped into babies' incubators for three hours a day. The idea was to recreate the sounds that the babies would have been hearing in the womb if they had not been born early.

The result? The babies who were able to hear their mothers performed better than those who didn't, Dr. Lahav explained at the American Association for the Advancement of Science over the weekend. Toward the end of their hospital stay, babies who had heard recordings of their mothers' voices paid more attention to a female speaker than babies who had not heard the recordings, based on eye-tracking and pupil-dilation measurements (two indicators that reveal how well preemies are developing).

Dr. Lahav said the results go a long way in proving that the everyday sounds of mothers are "part of the original recipe for how we should cook premature babies up to full maturation."

Hollee Actman Becker is a freelance writer, blogger, and a mom. Check out her website holleeactmanbecker.com for more, and follow her on Twitter at @holleewoodworld.