Many pregnant women understand the risk factors for their baby – they know not to smoke, drink alcohol, eat pate or go skydiving. However, few are aware of how excessive noise can impact on an unborn baby’s hearing, and even its overall health.
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Baby’s development and sounds
Being inside the womb can muffle some sounds to a developing baby, but research has proven that a woman’s body is by no means an effective soundproof barrier. In fact, babies can start to hear noises from outside the womb as early as 16 weeks into pregnancy. Their inner, outer and middle ears are developed by 24 weeks, and most babies can react to noises from this point onwards.
Positive impact of sound
The fact that babies hear sounds from the second trimester can be used to good effect. Parents who talk to their unborn child can start to build bonds from an early stage, and listening to soothing sounds such as soft music can help the growing foetus to relax.
On the other hand, excessive levels of sound can cause more harm than good to an unborn child. Studies have shown that exposure to sounds of 90-100 decibels or more can adversely affect an unborn baby’s hearing. This sound level is equivalent to the noise a chainsaw makes.
Lower noise frequencies are especially damaging to an unborn child. Even short bursts of loud sound can cause harm to a baby’s hearing, while sudden loud sounds can startle the foetus.
What’s more, babies who have been exposed to loud sounds during pregnancy are at a higher risk of being born prematurely and with a low birth weight. Noise pollution can also cause stress to the expectant mother and child, and may cause their blood pressure and heart rate to increase.
Avoiding loud noise
It stands to reason that any pregnant woman should avoid loud noise as much as possible, in order to protect her own health and that of her baby, but what can a woman do if noise is part and parcel of her job?
Wearing protective equipment will safeguard the hearing, but it won’t stop sounds travelling through the womb to the baby’s sensitive, developing ears. Therefore, pregnant women should avoid situations at work, or elsewhere, where noise levels are excessive.
Employers are required under the EU 2005 Noise Regulations and UK Noise at Work Regulations to assess how noise impacts pregnant employees. If any risks are identified, the employer must act to alter working conditions so that pregnant staff aren’t exposed to loud noise.
Although there’s no universal agreement on what constitutes a safe level of noise for pregnant women, experts in Sweden claim that noise levels shouldn’t be greater than 80dB(A).
Expectant mothers exposed to sounds above this level should be moved to quieter areas for the duration of their pregnancy. Warning notices should be placed in areas where noise levels are high, so staff are aware of the risks when moving around the workplace. Areas of work where sudden, loud noises are a feature should be avoided by pregnant staff, as should those tasks where a worker has to lean up close to a machine that makes a low-frequency sound, such as a vibration or rumble.
Excessive sound can cause hearing problems, whether you’re pregnant or not. That’s why noise control is essential in many environments. If you’re seeking effective solutions that will keep unwanted sounds at bay, take a look at the range of high-quality options from Sound Planning – we are the professional route to a quieter life!