Chinese and American scientists have found that nearly one million babies worldwide are stillborn each year because of high levels of air pollution inhaled by their mothers. This means that about half of all stillbirths are due to air pollution. For the first time, the authors of a new study published in the journal Nature have been able to determine the specific impact that high concentrations of airborne microparticles have on the number of cases of fetal death.
The researchers examined data on 45,000 births that occurred between 1998 and 2016 in 54 low- and middle-income countries. They extended the established correlation to 137 countries in Asia, Africa, and Latin America, which account for 98% of all births worldwide that end in stillbirth. Russia is not included in these 137 countries.
According to the World Health Organization data for 2019, in Russia there are on average 3.8 cases of stillbirths per thousand births, while in the countries that were the subject of the study, this ratio ranges from 10 to 30 stillbirths per thousand live births. This compares with 3 stillbirths per thousand live births in the United Kingdom and the United States.
The study examines only the relationship between levels of PM 2.5 (tiny particles that can enter the human bloodstream) in the air and fetal mortality. The authors of the study did not attempt to show exactly how PM2.5 microparticles, most commonly found in the air from the burning of fossil fuels, affect the body of a mother and her unborn child. In recent years, however, several other studies have been devoted to this topic, showing in particular how small particles from the mother’s lungs cross over into the placenta. These particles have also been found in the lungs, liver and brain of embryos.
India is one of the countries with the highest levels of PM2.5 in the air. We explain quickly, simply, and clearly what happened, why it matters, and what happens next. Episodes The end of the story. Podcast Advertising. If they get into the placenta, they can cause “irreparable damage to the embryo” or prevent the mother’s body from supplying it with oxygen, the authors of the current study suggest.
According to the World Health Organization recommendations updated in 2021, the annual average concentration of PM 2.5 particles should not exceed 5 µg per cubic meter, while the daily average should not exceed 15 µg. All of the mothers whose pregnancies were included in the current study lived in regions where PM 2.5 exceeds the WHO recommended level.
“Reducing PM 2.5 to the WHO recommended level can prevent a significant number of stillbirths,” said Tao Yue, a scientist at Peking University who led the study. In its 2020 report on stillbirth, Unicef called the phenomenon a “tragedy that is being overlooked”.
According to Tao Yue, many countries are trying to prevent stillbirths through medicine, but environmental risk factors are often not considered. “The government policy of air purification implemented by China and some other countries can prevent cases of stillbirth,” the study’s commentary states. “In addition, personal protective measures such as masks and air purifiers can protect women in the high-risk category. In addition, it is better to avoid going outdoors when air pollution is particularly high.”
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