Objectives A recent discussion surrounding the extension of antenatal corticosteroid (ACS) use beyond 34 weeks of gestation did not include the subgroup of infants of diabetic mothers (IDM). We aimed to examine the association between ACS exposure and outcomes in neonates born at term and at near-term gestation in a large cohort of IDMs. Methods We selected 13976 eligible near-term and term infants who were included in the PEARL-Peristat Perinatal Registry Study (PPS). We assessed the association of ACS exposure with neonatal outcomes in a multivariate regression model that controlled for diabetes mellitus (DM) and other perinatal variables. Results The incidence of DM was 28% (3,895 of 13,976) in the cohort. Caesarean section was performed in one-third of the study population. The incidence of ACS exposure was low (1.8%) and typically occurred>2 weeks before delivery. The incidence rates of respiratory distress syndrome (RDS)/ transient tachypnoea of newborns (TTN), all-cause neonatal intensive care unit (NICU) admissions, NICU admissions for hypoglycaemia, and low 5-min Apgar scores were 3.5, 8.8, 1.3, and 0.1%, respectively. In a multivariate regression model, ACS was associated with a slight increase in NICU admissions (OR: 1.44; 95% CI: 1.04-2.03; p=0.028), but not with RDS/TTN. Conclusions Although the low exposure rate was a limitation, ACS administration did not reduce respiratory morbidity in near-term or term IDMs. It was independently associated with an increase in NICU admissions. Randomized controlled trials are required to assess the efficacy and safety of ACS administration in diabetic mothers at late gestation.