Music triggers powerful physical reactions in pregnant women

Researchers have discovered that pregnant women compared to their non-pregnant counterparts rate music as more intensely pleasant and unpleasant, associated with greater changes in blood pressure.

Music appears to have an especially strong influence on pregnant women, a fact that may relate to a prenatal conditioning of the fetus to music.

For their study, the Max Planck researchers played short musical sequences of 10 or 30 seconds' duration to female volunteers. They changed the passages and played them backwards or incorporated dissonances. By doing so, they distorted the originally lively instrumental pieces and made listening to them less pleasant.

The pregnant women rated the pieces of music slightly differently, they perceived the pleasant music as more pleasant and the unpleasant as more unpleasant.

The blood pressure response to music was much stronger in the pregnant group. Forward-dissonant music produced a particularly pronounced fall in blood pressure, whereas backwards-dissonant music led to a higher blood pressure after 10 seconds and a lower one after 30 seconds.

"Thus, unpleasant music does not cause an across-the-board increase in blood pressure, unlike some other stress factors", says Tom Fritz of the Max Planck Institute in Leipzig. "Instead, the body's response is just as dynamic as the music itself."

According to the results, music is a very special stimulus for pregnant women, to which they react strongly. "Every acoustic manipulation of music affects blood pressure in pregnant women far more intensely than in non-pregnant women", says Fritz.

The researchers suspect that foetuses are conditioned to music perception while still in the womb by the observed intense physiological music responses of the mothers.