Maternal infection during pregnancy contributes to childhood obesity

Maternal infection, but not antibiotic use, during pregnancy bears a heightened risk of childhood obesity, a study suggests.

The analysis included 145,393 mother-child dyads, grouped into four comparison cohorts, as follows: (1) unexposed controls (no infection/no antibiotic use), (2) untreated infection (had infection, but received no antibiotics), (3) treated with infection (had infection and treated with antibiotics), and (4) treated without infection (received antibiotics without evidence of an infection during pregnancy, likely due to prophylactic treatment).

In an analysis controlling for confounders using propensity score methodology, maternal antibiotic use during pregnancy had null effect on the risk of childhood obesity once underlying infection was controlled for (odds ratio [OR], 0.97, 95 percent confidence interval [CI], 0.92–1.01). Likewise, there was no risk increase observed with timing of use or use of broad-spectrum antibiotics, nor a dose-response relationship.

On the other hand, maternal untreated infection (without antibiotic use) during pregnancy carried a significant increase in the risk of childhood obesity compared with unexposed control (OR, 1.09, 95 percent CI, 1.03–1.16). The association was more pronounced for group B streptococcal (GBS) positive infection (OR, 1.16) than GBS negative infections (OR, 1.08).

The results were consistent in a discordant sibling study, which allowed additional control of unmeasured confounders including genetic, maternal intrauterine and familiar factors.

In light of the findings, researchers emphasized that while use of antibiotics should always be judicious, maternal infections during pregnancy should be treated to prevent childhood obesity.