Abstract
Studies in mice suggest that early life represents a critical time window, where antibiotics may exert profound and lasting effects on the gut microbiota and metabolism. We aimed to test the hypothesis that prenatal antibiotic exposure is associated with increased risk of childhood overweight in a population-based cohort study. We linked 43,365 mother-child dyads from a nationwide cohort of pregnant women and their offspring to the Danish National Prescription Registry. Linear and logistic regression models were used to examine associations between prenatal exposure to antibiotics and BMI z-score and overweight (including obesity) at age seven and 11 years. Prenatal antibiotic exposure and childhood overweight were both associated with high pre-pregnancy BMI, maternal diabetes, multi-parity, smoking, low socioeconomic status, high paternal BMI, and short duration of breastfeeding. After adjustment for confounders, no associations were observed between prenatal antibiotic exposure and odds of overweight at age seven and 11 years. Whereas no association was observed between broad-spectrum antibiotics and overweight at age 11 years, exposure to broad-spectrum antibiotics was associated with higher odds of overweight at age seven years with an odds ratio of 1.27 (95% CI, 1.05–1.53) for ampicillin and an odds ratio of 1.56 (95% CI, 1.23–1.97) for amoxicillin. As we did not account for underlying infections, the observed associations with early childhood overweight could be explained by confounding by indication. In conclusion, our population-based study suggests that prenatal exposure to narrow-spectrum antibiotics is not associated with overweight in offspring. Exposure to some broad-spectrum antibiotics may increase the odds of overweight in early childhood, but the association does not persist in later childhood.
Highlights
Compared to 37,864 mothers who were not included in the study due to missing information on childhood body mass index (BMI), the women who were included were slightly less likely to receive antibiotics, had slightly lower pre-pregnancy BMI, lower prevalence of smoking, higher socioeconomic status, and longer duration of breastfeeding (Supplementary Table 2)
Exposure to antibiotics in pregnancy was associated with higher pre-pregnancy BMI, higher prevalence of maternal diabetes, multi-parity, higher prevalence of smoking, lower socioeconomic status, higher paternal BMI, and shorter duration of breastfeeding (Table 1)
Our nationwide study of more than 40,000 mother-child pairs followed prospectively suggests that prenatal exposure to narrow-spectrum antibiotics is not associated with overweight in offspring
Summary
The gut microbiota of children is established during the first few years of life, which represents a critical time window, where the gut microbiota is especially vulnerable to external influences, including antibiotics[3] As neonates acquire their microbes from their mother during delivery[3], and since several studies have suggested that the gut microbiota contributes to metabolic diseases[4], it has been hypothesized that exposure to antibiotics during pregnancy alters the composition of the founding microbiota of the neonate and thereby contributes to development of childhood overweight and obesity[3].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
