Prenatal antibiotics increase risk of OM and ventilation tubes in children

A recent study found that the maternal use of antibiotics during pregnancy appears to increase the risk of otitis media (OM) and the placement of ventilation tubes in the offspring, particularly when administered later in the pregnancy. Although antibiotics can sometimes be a necessary therapeutic intervention, clinicians should be prudent and proceed with caution when considering appropriate antibiotic therapy in this patient population.

“Our findings encourage a more careful assessment of the need for antibiotics,” says Hans Bisgaard, MD, DMSc, professor of Pediatrics and founder and head of the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC), Herlev and Gentofte Hospital, University of Copenhagen, Denmark. “Often, ordinary symptoms of the pregnancy may be mistaken for symptoms of urinary tract infection. Therefore, antibiotics should be restricted to documented infections,” he says.

Using the data from 700 children in the COPSAC 2010, an ongoing unselected birth cohort study, Bisgaard and colleagues conducted an observational, single-center study to investigate the association between antibiotic intake during pregnancy and the development of OM and placement of ventilation tubes in the offspring. Mothers were recruited from 2008 to 2010 at pregnancy week 24, and information on their antibiotic use and other exposures during their pregnancy was collected prospectively from interviews and further validated in national registries. Children were included at age 1 week and followed prospectively by pediatricians with regularly scheduled follow-up visits out to 3 years, during which time OM episodes were recorded in a diary. Information regarding children’s ventilation tubes also was obtained from national registries.

Of the 700 children, 514 had complete diary information and were included in the OM analysis. National registry data had information on 699 of the children on treatment with ventilation tubes; these were included in the analysis on ventilation tubes. There was 37% maternal antibiotic use during pregnancy, and this was associated with an increased risk of OM in children. The administration of antibiotics in the third trimester was particularly associated with a higher risk of receiving ventilation tubes. Moreover, the data revealed that the risk of OM increased with increasing number of antibiotic treatments.

Compared with mothers who did not receive antibiotics, the incidence of OM was statistically significantly increased in mothers treated with antibiotics for respiratory tract infection, specifically in the third trimester, and mothers treated with antibiotics in the second trimester.

The administration of antibiotics late in pregnancy is clearly implicated in the development of OM and the placement of ventilation tubes and, according to Bisgaard, these complications are believed to be attributed to the potential vertical transmission of an unfavorable microbiome from mother to child during birth. Furthermore, the mother’s use of antibiotics after birth was not associated with OM in the child, suggesting that the observations are indeed a pregnancy phenomenon and not just caused by an inherited higher risk of infections.

“This study and others suggest that the transmission of the mother’s microbiome is important for the programming of a healthy immune system in the child,” Bisgaard says. “As an example we previously demonstrated the risk of childhood asthma increases by approximately 25% in children born by a planned cesarean [delivery]. Our current research is sequencing the microbiome from the pregnant mother and newborn child aiming to define the ‘healthy microbiome,’ hopefully allowing this to be given to the newborn child,” he says.

In order to help circumvent these potential issues, Bisgaard recommends that clinicians steer clear from broad-spectrum antibiotics during pregnancy and suggests the primary use of simpler antibiotics whenever possible in this patient population.

Dr Bisgaard reports no relevant disclosures.

Dr Petrou is a freelance medical writer based in Budapest, Hungary. He has nothing to disclose in regard to affiliations with or financial interests in any organizations that may have an interest in any part of this article.