Antibiotics During Pregnancy Linked to Childhood Asthma: Study

Use of antibiotics during pregnancy may cause the baby to develop asthma later in their childhood, according to a new Danish study. 

Research published online by the The Journal of Pediatrics on November 8 found children born to mothers who received antibiotics during the third trimester of pregnancy had an increased risk of developing asthma compared to mothers who did not use antibiotics during pregnancy.

The findings confirmed children whose mothers used antibiotics at any time during pregnancy also had an increased risk for asthma hospitalization and prescription corticosteroid need.

The Copenhagen Prospective Study on Asthma in Childhood followed 411 children whose mothers had asthma, until 5 years of age. Children born to mothers using antibiotics for non-respiratory infections during pregnancy were twice as likely to develop asthma.

Researchers confirmed the findings by examining data from a larger Danish study which followed more than 30,000 children born to mothers who had taken antibiotics during pregnancy. More than three percent of the children were hospitalized for asthma related problems by the age of five. The study also found that 17% of the children had a greater risk of hospitalization from asthma and an 18% increased risk of corticosteroid use in children whose mothers used antibiotics.

Scientists believe the findings of the Danish cohort study support the theory linking bacterial ecology and asthma. The body has a natural bacteria which aids in warding off the development of certain diseases, such as asthma. According to the theory, antibiotic use can interfere with the natural bacteria, causing a child to develop asthma.

“We speculate that mothers’ use of antibiotics changes the balance of natural bacteria, which is transmitted to the newborn, and that such unbalance bacteria in early life impact on the immune maturation in the newborn,” said Hans Bisgaard, study co-author and professor at the University of Copenhagen.

The results of the studies do not conclusively prove that the antibiotic use caused an increased risk of the development of asthma; however, a recent study concerning Acetaminophen use in infants also found a link between the use of the medication, commonly referred to as Tylenol, and a development of childhood asthma.

Both studies highlight that pregnancy is a critical time for the development of a child’s immune system and researchers indicate that further studies are necessary on the use of medications during pregnancy.