Antibiotics are the most commonly prescribed drugs during pregnancy. The long-term health risks to children associated with prenatal antibiotic exposure are uncertain.

To identify the association between prenatal antibiotics and adverse long-term health outcomes in children.

A systematic search was done to identify original studies investigating the association between prenatal antibiotic exposure and adverse long-term health outcomes in children. Studies were excluded if: (i) antibiotics were only given during delivery or (ii) the outcome was present before antibiotic exposure.

We included 158 studies, reporting 23 outcomes in 21,943,763 children, in our analysis. For the following adverse health outcomes, there was a significant association with antibiotic exposure found in two or more studies: atopic dermatitis (OR 1.27, 95% CI 1.06–1.52, p=0.01), food allergies (OR 1.25, 95% CI 1.09–1.44, p<0.01), allergic rhinoconjunctivitis (OR 1.16, 95% CI 1.15–1.17, p<0.01), wheezing (OR 1.39, 95% CI 1.14–1.69, p<0.01), asthma (OR 1.36, 95% CI 1.24–1.50, p<0.01), obesity (OR 1.36, 95% CI 1.12–1.64, p<0.01), cerebral palsy (OR 1.25, 95% CI 1.10–1.43, p<0.01), epilepsy or febrile seizure (OR 1.16, 95% CI 1.08–1.24, p<0.01), and cancer (OR 1.13, 95% CI 1.01–1.26, p=0.04).

Although causality cannot be implied, these findings support antibiotic stewardship efforts to ensure judicious use of antibiotics during pregnancy to avoid potential long-term health risks.