Prenatal antibiotic exposure linked to childhood asthma
Prenatal exposure to antibiotics is associated with an increased risk for childhood asthma, according to study findings published in Clinical Infectious Diseases.
“As much as [antibiotics are a] lifesaving benefit for a mother and fetus, clinicians should critically evaluate the adverse effects of antibiotics, including the short-term effects on pregnant women, as well as potential long-term effects on the newborn,” Kedir N. Turi, PhD, research assistant professor at Vanderbilt University School of Medicine, told Healio.
Turi and colleagues studied 84,214 mother-child dyads continuously enrolled in the Tennessee Medicaid Program between 1995 and 2003, including 64% (n = 54,141) in which the child was exposed to a prenatal antibiotic, for a total of 104,082 prenatal antibiotic courses. Among all children, 14% (n = 11,889) developed asthma by the age of 6 years.
They classified dyads into groups based on the trimester of prenatal exposure. For children who were exposed to prenatal antibiotics during the first trimester only compared with children who were not exposed at all, the odds of developing childhood asthma increased by 17% (adjusted OR = 1.17; 95% CI: 1.09-1.25). The odds increased by 9% for children exposed in the second trimester (aOR = 1.09; 95% CI: 1.01-1.16) and by 11% in the third trimester (aOR = 1.11, 95% CI: 1.04, 1.19). Children who were exposed to prenatal antibiotics during multiple trimesters faced a 38% increased odds of childhood asthma (aOR = 1.38, 95% CI: 1.32, 1.45).
“We knew that prenatal antibiotics were associated with childhood asthma based on the result from other studies,” Turi said. “However, we did not expect early pregnancy as a critical time period among children whose mothers used at least two courses of antibiotics.”
Turi said other studies in humans and animals have shown similar results.
One possible mechanism is that “early antibiotic use disrupts maternal gut microbiome and possibly colonization of fetal environment microbial colonization, which provide metabolites and training for fetal immune development respectively,” he said. “Disruption of the diversity and function of the developing microbiome metacommunity can affect immune system development, cause immune dysregulation and increase the risk of asthma in the offspring.”
According to Turi, the development of asthma is due to an interaction of genetics and environmental exposure beginning at conception. Although the child’s predisposition to asthma cannot be modified, exposure to modifiable environmental risks — like prenatal antibiotics — can.
“Clinicians should be mindful of the long-term effects of prenatal antibiotics on newborns and scrutinize the need for prescribing prenatal antibiotics to minimize the adverse effects and maximize the benefits, especially among women with asthma,” he said. – by Ken Downey Jr.
Disclosures: Turi reports no relevant financial disclosures.