According to a study by the Karolinska Institute, women with asthma are more likely to suffer from preeclampsia and have a higher risk of having underweight children. These and other complications during pregnancy and childbirth cannot be explained by hereditary or environmental factors.
Asthma is a common disease caused by chronic inflammation in the lungs with symptoms such as cough and shortness of breath and affects 8-10% of women of childbearing age in Sweden.
Using Swedish birth data and drug prescriptions, the researchers were able to study the association between asthma in pregnant women and pregnancy/delivery outcomes. Between 2001 and 2013, studying more than a million newborns and more than seven hundred thousand women, they found that 10% of children born had a mother with bronchial asthma.
4% of all pregnant women develop preeclampsia. The risk of preeclampsia is 17% higher in women with asthma than in women without it, the authors noted. In addition, women with asthma were more likely to have underweight babies or had to have caesarean sections, and their pregnancies were shorter.
To find out if the complications could be attributed to hereditary or environmental factors, the researchers also identified cousins ​​and sisters of these women who did not have asthma and gave birth during the same period. Comparing the groups, they found correlations between maternal asthma and complications during pregnancy and childbirth.
It seems that it is asthma itself that causes these complications, the authors note. This means that well-controlled asthma during pregnancy can reduce the relative prevalence of complications during pregnancy and childbirth.