Air pollution linked to ‘silent’ miscarriages
Pregnant women who have been exposed to high levels of air pollution are more likely to suffer a so-called silent miscarriage, according to a new study from China. A “silent” or “missed” miscarriage occurs when a fetus has died but there are no physical signs that anything has gone wrong, leading parents to think that the pregnancy is progressing normally. For the study, researchers looked at the clinical records of more than 250,000 pregnant women living in Beijing—which has one of the world’s highest levels of air pollution— from 2009 to 2017. They assessed the women’s exposure, at work and at home, to four types of pollutants: a deadly fine particulate matter known as PM2.5, sulfur dioxide, ozone, and carbon monoxide. Overall, 6.8 percent of the women suffered silent miscarriages during their first trimester. After controlling for factors including age and occupation, the scientists concluded that the higher a woman’s pollutant exposure, the higher her risk of a silent miscarriage. Tom Clemens, a researcher at the University of Edinburgh who wasn’t involved in the paper, tells The New York Times that previous studies have suggested a “link between air pollution and pregnancy outcomes in general, particularly the risk of a premature birth and a low-weight baby.” But, he says, this is one of the first pieces of research to connect particle pollution and miscarriage, “so in that sense it’s very important.”