Over 90% of preterm neonates are, often empirically, exposed to
antibiotics as a potentially life-saving measure against
sepsis. Long-term outcome in association with
antibiotic exposure (
NABE) has insufficiently been studied after
preterm birth. We investigated the association of
NABE-duration with early-childhood developmental and health outcomes in preterm-born children and additionally assessed the impact of GA on outcomes. Preterm children (GA < 30 weeks) participating in a multicenter cohort study were approached for follow-up. General expert-reviewed health questionnaires on respiratory, atopic and gastrointestinal symptoms were sent to parents of children > 24 months' corrected age (CA). Growth and developmental assessments (Bayley Scales of Infant and Toddler Development (BSID) III) were part of standard care assessment at 24 months' CA. Uni- and multivariate regressions were performed with
NABE (per 5 days) and GA (per week) as independent variables. Odds ratios (OR) for health outcomes were adjusted (aOR) for confounders, where appropriate. Of 1079 infants whose parents were approached, 347 (32%) responded at a mean age of 4.6 years (SD 0.9). In children with
NABE (97%),
NABE duration decreased by 1.6 days (p < 0.001) per week of gestation. Below-average gross-motor development (BSID-III gross-motor score < 8) was associated with duration of
NABE (aOR = 1.28; p = 0.04). The aOR for
constipation was 0.81 (p = 0.04) per gestational week. Growth was inversely correlated with GA. Respiratory and atopic symptoms were not associated with
NABE, nor GA. We observed that prolonged
NABE after
preterm birth was associated with below-average gross-motor development at 24 months' CA, while a low GA was associated with lower weight and stature Z-scores and higher odds for
constipation.