Unlike prior studies, we used antibiotics as proxy for immune function.

We found no association between maternal or child PFAS and childhood antibiotic use.

There is a high risk that this is due to a lack of specificity in the outcome.

Per- and polyfluoroalkyl substances (PFAS) have been associated with an increased risk of infectious diseases. We aimed to investigate if in utero and early childhood exposure to PFAS was associated with the number of antibiotic prescriptions up to eight years of age.

Among 2448 singleton mother-child pairs from the Odense Child Cohort, 1425 had sufficient information on key variables and were included in the primary analysis. Information on redeemed antibiotic prescriptions from birth to eight years of age was obtained from the Danish National Prescription Registry. Longitudinal discrete-time Poisson models were used to quantify the relationship between PFAS and the number of antibiotic prescriptions redeemed. Analyses were carried out separately for PFAS measured in the mother during pregnancy and in the child at 18 months of age. Missing information was imputed using Multiple Imputation by Chained Equations.

We observed no differences in the number of antibiotic prescriptions in the first eight years of life when comparing median and high PFAS concentrations measured in both pregnancy and at 18 months of age (rate ratio PFOA 1.01, 95 % confidence interval 0.94–1.08; PFOS 1.08, 0.98–1.19; PFNA 1.00, 0.94–1.07; PFDA 0.99, 0.94–1.04; PFHxS 1.02, 0.98–1.07).

We found no association between in utero or early childhood PFAS concentrations and number of antibiotic prescriptions up to eight years of age. Antibiotic prescriptions may be an unspecific marker of childhood infections, hampering the possibility to observe an association with PFAS exposure.

Environmental epidemiology

Infectious diseases

Antibiotics

Perfluoroalkyl acids

© 2025 The Authors. Published by Elsevier GmbH.