Many moms or pregnant women ask themselves the following question: Can loud noise affect their babies during pregnancy? And the answer is yes; noise can affect the baby during pregnancy. We refer to loud noises, which come from planes, traffic jams, concerts, machinery, etc.
Well, there is a special situation that we cannot forget and in which noise, once again, plays a dangerous role: pregnancy.
Babies can hear almost perfectly in the second trimester of pregnancy. Sound stimulation has multiple benefits for the development of the fetus, but what happens when these stimuli are in the form of noise? When can noise pose a long-term risk to the fetus?
The impact of noise on pregnancy
The ear is one of the first senses to fully develop during pregnancy. It is known that already at 16 weeks (4 months), the baby can hear, and by 24 weeks of gestation (6 months), the inner, middle, and outer ears are mature enough to process the sound information that comes through the ear. uterus.
Sounds reach the baby and, in fact, are a necessary stimulus for the development of his central nervous system and his learning to process sounds. Therefore, moms and dads are advised to talk, sing, and play music to the fetus from week 20 to help their hearing development and increase brain connections.
They arrive, yes, somewhat minimized by the physical barrier of the mother’s gut, uterus, and amniotic fluid, and by the fact that the baby’s fluid-filled environment means that the eardrum and middle ear are not yet doing their job as sound amplifiers.
The maternal “sound filter” (combination of skin, muscle, uterus, and amniotic fluid) typically results in a 20–35 decibel decrease (to give you an idea, that’s the sound level of gentle surf) of the sound that finally comes to the baby.
Inside the womb, fetuses mainly hear the heartbeat of their mothers, the noises of the intestines, the palpitation of the arteries, the voice of the mother, and what happens outside. Although the sounds reach him in an attenuated way, he knows how to react to them. For example, when he perceives loud noises from outside, he changes his heart rate or moves, showing that he does not like the sound.
But what about the noise? When we talk about noise, we understand an undesirable sound that, in some way, alters Not only the intensity of the sound matter but also its frequency (hertz). It is known, for example, that the womb filters high frequencies better, so low frequencies reach the fetus more.
Pleasant sounds:
With pleasant sounds, not classified as ‘noises’, the opposite happens, and the baby can have great benefits; for example, calm music at a level of less than 70 dB can calm the baby as well as the mother and give her that feeling of calm and serenity. On the contrary, loud music would not generate that sensation.
Therefore, it is essential that we take into account all these data in our work or in another environment since music outside normal limits can affect our health, and in the case of pregnant women, it can also affect the fetus.
