Same Kaiser Permanente research team found similar results around infection in infants in 2016
Women who had an untreated infection during pregnancy were more likely to have a child who later went on to be obese than pregnant women who never had an infection, new research from Kaiser Permanente finds.
The study, published in the International Journal of Obesity on December 5, also found no association between antibiotic use by pregnant women and the obesity risk of their children. This adds to a growing body of research that suggests infection, not antibiotics, is the significant factor in a suspected link between the microbiome of early childhood and childhood obesity later on, said lead author De-Kun Li, MD, PhD, a research scientist with the Kaiser Permanente Division of Research.
These findings, Li said, remove some uncertainties for clinicians regarding antibiotic treatment in pregnant women and infants when appropriate. “The most important message is that while use of antibiotics should always be judicious and based on clinical necessity, clinicians shouldn’t be worried about prescribing antibiotics, as the infection is a greater concern than the antibiotic in relation to childhood obesity,“ Li said.
At the same time, Li emphasized that this work should be replicated by other researchers.
The study examined 145,393 mothers and their children who were members of Kaiser Permanente Northern California between 2007 to 2015, retrospectively examining medical records to compare groups of pregnant women with and without diagnosed infections and antibiotic use. The researchers were also able to control for potential confounding factors such as maternal smoking, pre-pregnancy body mass index, race/ethnicity, and breastfeeding.
The analysis found mothers diagnosed with infections during pregnancy who were not prescribed antibiotics were about 9% more likely to have a child who went on to be obese compared with women who did not have an infection diagnosis during pregnancy; the association was stronger (16%) for mothers confirmed to have a group B streptococcal infection.
To add rigor to the analysis, Li and colleagues examined records for 6,256 discordant sibling pairs, children of the same mother whose infection and antibiotic experience was different during the two pregnancies. The sibling examination had similar results to those of the overall study population.
The study follows on previous research by Li and his team published in November 2016 in Lancet Diabetes & Endocrinology, which also sought to separate the effect of infection from that of antibiotic use, but in infants rather than mothers. The Lancet study had similar findings; children diagnosed with an infection during their first year of life who were not treated with antibiotics were about 25% more likely to become obese compared with children without infections. The 2016 study also found no such association with antibiotic use in the infants.
The research adds to the evidence base around prenatal risk factors for childhood obesity, including how the microbiome (bacteria residing largely in the gut) may affect children’s development. Researchers are interested in identifying factors that contribute to both the child’s microbiome and that of the mother during pregnancy and delivery that may influence the long-term health of the child.
The study was funded by the Kaiser Permanente Center for Effectiveness & Safety Research.
Co-authors were Hong Chen, MPH, Jeanette Ferber, MPH, and Roxana Odouli, MSPH, all of the Division of Research.