Early-life antibiotics have been associated with childhood overweight and obesity. We investigated how the timing of early-life antibiotic exposure is associated with childhood overweight and obesity. Antibiotic exposure in the first two years of life was associated with overweight and obesity. No similar associations were found with antibiotic exposure before pregnancy, during pregnancy, or in the perinatal period. Interventions aiming to reduce obesity-associated effects should focus on the first two years of life.
Ainonen et al. (Sat,) studied this question.