Pregnant women who take paracetamol to treat pain, fever or flu are likely to have their unborn child developing asthma, findings of a new study suggest.

The study, which was published in the International Journal of Epidemiology on Feb. 9, has shown that exposure to acetaminophen, which is sold under the brand name Tylenol, during pregnancy was linked to increased risk for asthma in young children.

Maria Magnus, from the Norwegian Institute of Public Health, and colleagues looked at several conditions during pregnancy, for which some of the expectant mothers took the over-the-counter medicine.

The researchers then compared the data against the rates of asthma developing in more than 114,000 children involved in the study when they turn 3 and 7 years old.

The results revealed that 5.7 percent of the children had asthma at 3 years old and 5.1 percent had asthma at age 7.

The researchers likewise observed a consistent link between the children who have asthma at 3 years old and exposure to paracetamol during pregnancy. The strongest link was observed in children whose mother used paracetamol during pregnancy for more than one health problem.

The association between the drug and asthma risk among the children was similar regardless if the pregnant mother took the medicine for pain, fever or flu. This suggests that the drug itself and not the underlying condition is behind this link.

The authors of the study, however, said their findings do not provide a causal relationship and that the results of the study do not warrant changes on pain relief guidelines among pregnant women.

"This study provides evidence that prenatal and infant paracetamol exposure have independent associations with asthma development," the researchers wrote. "Our findings suggest that the associations could not be fully explained by confounding by indication."

Experts said that regardless of the findings, acetaminophen remains to be the safest treatment option for pregnant women to fight pain and fever.

Jennifer Wu, from Lenox Hill Hospital in New York City, advised pregnant women to stay away from aspirin or ibuprofen given the risks associated with these medications.

ⓒ 2021 All rights reserved. Do not reproduce without permission.