What is Known: • There remains a difference in outcomes of male and female infants born prematurely. • Prematurely born male infants were more likely to receive postnatal corticosteroids and a greater number of courses but had similar outcomes compared to female infants.

What is New: • Postnatal corticosteroids have long-term adverse effects. Such outcomes should be considered when weighing up the risk–benefit ratio of prescribing postnatal corticosteroids, particularly in very prematurely born male infants.