The results of a study of almost 500,000 women indicate that taking paracetamol or other painkillers during pregnancy does not increase the risk of asthma in children. Research sponsored by the European Lung Foundation does support earlier findings that women taking paracetamol during pregnancy are more likely to have children who develop asthma, but it also suggests that the painkillers are not the cause of this increase.

Several studies in different countries have documented the link between an increased risk of asthma in children and paracetamol use during pregnancy, but very little research exists regarding the use of other painkillers during pregnancy and the subsequent risk of asthma in children.

The investigators studied 492,999 Swedish mothers and their children, looking into data on prescriptions for different types of painkillers during pregnancy and comparing these data with rates of asthma diagnosis in the children. They also studied family medical history.

They found that children born to mothers who had been prescribed paracetamol during pregnancy did have an increased risk of asthma, but the risk was similar when women had been prescribed migraine medication or opioids, such as codeine and tramadol. The increase in risk for asthma at 5 years of age was 42% for codeine, 48% for migraine medication, and 50% for paracetamol.

Shaheen SO, Lundholm C, Brew BK, Almqvist C. Prescribed analgesics in pregnancy and risk of childhood asthma. Eur Respir J. 2019;53(5):pii:1801090. doi: 10.1183/13993003.01090-2018.