The researchers found that approximately 349,681 miscarriages each year in India, Bangladesh and Pakistan were associated with poor air quality.
But the study is believed to be the first of its kind to quantify the effect of environmental pollution on pregnancy loss in South Asia – one of the most polluted regions on Earth – and the authors say their findings are important for improving public and maternity health. especially in low-income countries.
“South Asia has the largest burden of pregnancy loss globally and is one of the most polluted regions in the world with PM2.5. Our findings suggest that poor air quality could be responsible for a considerable burden of pregnancy loss in the region, providing additional justification. for urgent action to combat dangerous levels of pollution, “said the study’s lead author, Dr. Tao Xue, who is an assistant professor at Peking University, China.
PM2.5 is a tiny particulate pollution that can move deep into the lungs when inhaled and enters the bloodstream. Particles, made up of dust, dirt, soot or smoke, come from construction sites, unpaved roads, fields, chimneys or fires and may contain various chemicals. But most particles are a mixture of pollutants from power plants, industrial emissions and vehicles.
Researchers have focused on these small particles of pollution. They found that between 2000 and 2016, 7.1% of pregnancy losses in South Asia were attributed to mothers exposed to air pollution that exceeded India’s current air quality standard of 40 micrograms per cubic meter of air.
Studies have found that expectant mothers in rural or older areas have a higher risk than young mothers in urban areas. And the loss of load associated with air pollution was more common in the northern plains of India and Pakistan.
To reach their conclusions, the researchers analyzed data from household health surveys from 1998 to 2016 and estimated exposure to pollution during pregnancy using satellites. They then created a model that examined how exposure to pollution increased a woman’s risk of miscarriage, taking into account maternal age, temperature and humidity, seasonal variations, and long-term trends in pregnancy loss.
The study included 34,197 women who had lost a pregnancy, including 27,480 miscarriages and 6,717 stillbirths. Of the pregnancy losses, 77% were from India, 12% from Pakistan and 11% from Bangladesh.
The authors say that lower air quality may increase the burden of miscarriage in low- and middle-income countries, so that improving pollution levels could reduce miscarriages and stillbirths and lead to direct improvements in gender equality.
“We know that losing a pregnancy can have mental, physical, and economic effects on women, including an increased risk of postnatal depressive disorder, infant mortality during subsequent pregnancy, and increased pregnancy-related costs, such as losing labor,” said the co-author Dr. Tianjia Guan, from the Chinese Academy of Medical Sciences and Peking Union College of Medicine.
The study warns that more research is needed to determine the causality between pollution and pregnancy loss, as they said survey data are subject to memory bias. Researchers have also failed to distinguish between natural miscarriage and abortions. He also notes that there have been reports of natural miscarriages due to stigmatization or ignoring very early miscarriages.