Classical music truly touches the heart, and it does so even before birth: a fascinating study led by the Institute of Cardiology Ignacio Chávez (Mexico) has shown how music can slow fetal heart rate, potentially offering benefits for development.

This is not the first research to demonstrate the wonderful effects of melodies; in fact, studies on the effects of prenatal music on unborn children have been ongoing for decades. Recently, a study published in BMC Pediatrics demonstrated that prenatal sound stimulation, including music and language, can form specific memory traces during the fetal period and influence the neonatal neural system.

Now, researchers have specifically focused on the effect of classical music on fetal heart rate, using mathematical analysis tools to identify patterns in heart rate variability.

Typical heart rate measurements average several beats over multiple seconds, while heart rate variability measures the time between individual beats and can provide information about the maturation of the fetal autonomic nervous system. Higher variability often indicates healthy development.

To test the effects of music on fetal heart rate, the research team recruited 36 pregnant women and played a couple of classical pieces for their fetuses, specifically The Swan by French composer Camille Saint-Saëns and Arpa de Oro by Mexican composer Abundio Martínez.

By connecting external heart rate monitors, the researchers were able to measure fetal heart rate responses to both songs, identifying changes in heart rate variability during and after music playback.

“Overall, we found that exposure to music produced more stable and predictable fetal heart rate patterns,” explains Claudia Lerma, who led the research. “We suppose that this temporary effect may stimulate the development of the fetal autonomic nervous system.”

Beyond the overall effects of music playback, researchers also examined differences between the two classical pieces. Although both were effective, the melody of the Mexican guitar had a more pronounced effect.

In general, researchers suggest that classical music could help promote fetal development.

“Our findings suggest that these changes in fetal heart rate dynamics occur instantly in short-term fluctuations,” says Eric Alonso Abarca-Castro, co-author of the study. “So, parents might consider exposing their fetuses to calm music. Parents who listen to relaxing music may stimulate and benefit the fetal autonomic system.”

The authors plan to continue exploring this effect by examining different genres and types of music to deepen their understanding. Specifically, to determine whether rhythmic or cultural variations elicit distinct fetal cardiac responses, they intend to increase sample sizes and expand their investigation to include a variety of musical styles beyond classical pieces.