[Prenatal rescue dose of betamethasone in the preterm infant with intrauterine growth restriction].

Antenatal corticosteroids reduce mortality and respiratory distress syndrome (RDS) in preterm newborns. These benefits decrease after a week of administration, recommending a rescue therapy if there is a new threat of premature delivery. Repeated administration of antenatal corticosteroids may have deleterious effects and their benefits are controversial in intrauterine growth restriction (IUGR). to verify the effects in the IUGR population of antenatal betamethasone rescue therapy on neonatal morbidity and mortality, RDS, and neurodevelopment at 2 years. Retrospective study including ≤ 34 weeks and ≤ 1,500g preterm newborns divided according to antenatal betamethasone exposure: Single-cycle (2 doses) vs Rescue therapy (3 doses). Subgroups were created for those ≥ 30 weeks. Both cohorts were followed up to 24 months of corrected age. The Ages & Stages Questionnaires (ASQ)® was administered to assess neurodevelopment. 62 preterm infants with a diagnosis of IUGR were included. The rescue therapy group compared with the single-dose group showed no differences in morbidity and mortality and less intubation rate at birth (p = 0.02), with no differences in respiratory support at 7 days of life. Preterm newborns ≥ 30 weeks exposed to rescue therapy showed higher morbidity and mortality (p = 0.03) and bronchopulmonary dysplasia (BPD) (p = 0.02), showing no differences in RDS. The rescue therapy group showed worse mean scores on the ASQ-3 scale, with no significant differences in cerebral palsy or sensory deficits. Rescue therapy reduces intubation at birth but does not reduce morbidity and mortality. However, at > 30 weeks, this benefit is not observed and the IUGR population exposed to rescue therapy presented more BPD and lower scores on the ASQ-3 scale at 2 years. Future studies should be aimed at the individualization of antenatal corticosteroid therapy.