17 July 2017

Stress during pregnancy can make exposure to smoking and air pollution worse

Researchers found that several common toxic chemicals had a much greater impact on pregnant women if they had high levels of stress.

Pregnancy involves a certain amount of stress, but if it gets too bad, hormones like cortisol and adrenaline can have lasting effect on mother and baby. 

More evidence of the harmful effects of stress comes from a pregnancy study. California researchers found that stress increases the risk that exposure to toxic chemicals in pregnancy will lead to a low birth weight baby.

"It appears that stress may amplify the health effects of toxic chemical exposure, which means that for some people, toxic chemicals become more toxic," said senior author Tracey Woodruff, a professor of obstetrics, gynaecology and reproductive sciences at the University of California, San Francisco.

The strongest connection involved smoking. High-stress women who smoked were about twice as likely to have a low birth weight baby as low-stress smokers, the researchers said in a UC Berkeley news release. Babies who are small for their gestational age can have serious health problems. The effects of air pollution on pregnant women were also magnified by stress, the researchers said.

Woodruff and colleagues at UC Berkeley reviewed 17 human and 22 animal studies that investigated the links between chemicals, stress and foetal development.

Increased risk of asthma and eczema

The review found that several toxic chemicals commonly found in the environment had a much greater impact on pregnant women if they had high levels of stress. The researchers measured stress by factors such as socioeconomic levels and years of education.

The researchers did not examine how stress and chemicals might interact to increase the risk of having a low birth weight baby. Nor can the study actually prove stress was the causative factor. The study was published in the journal PLOS ONE.

A previous Health24 article referred to another study, suggesting that stress during pregnancy can be linked to an increased risk of asthma and eczema. The researchers found that the likelihood of having asthma or eczema as a teenager was higher among children of mothers who experienced stressful life events during the second half of their pregnancies. 

Here are some practical tips on how to manage stress and anxiety during pregnancy:

  • Get enough sleep.
  • Try deep-breathing stretch exercises such as gentle yoga.
  • Incorporate low-impact cardiovascular exercise such as walking and swimming.
  • Eat a well-balanced, healthy diet to replenish your energy levels and overall well-being.

Read more:

Healthy lifestyle can lower the risk of gestational diabetes

Antidepressants during pregnancy have their benefits

Depression in pregnancy tied to preterm delivery


Live healthier

Lifestyle »

E-cigarettes: Here are five things to know

E-cigarettes have become hugely popular in the past decade, but a rash of vaping-linked deaths and illnesses in the US is feeding caution about a product that's already banned in some places.

Allergy »

Ditch the itch: Researchers find new drug to fight hives

A new drug works by targeting an immune system antibody called immunoglobulin E, which is responsible for the allergic reaction that causes hives.