A term gestation newborn developed respiratory distress. Which of the following would favour Respiratory distress syndrome (HIVID) ?
History of receiving antenatal corticosteroids
Air bronchogram on chest x–ray
Onset of distress after 6 hours of birth
Term birth
chest x-ray of an infant with RDS is characterized by atelectasis, air bronchograms, and a diffuse reticular-granular pattern commonly referred to as "ground glass". The chest x-ray may progress to a complete "white out" with severe disease.
About other options

Antenatal corticosteroids are given in pre-term (pre-mature) pregnancies not in term pregnancies. Further, antenatal corticosteroids are given to prevent RDS (HMD) --> after antenatal corticosteroids administration, risk of HMD is reduced.
Respiratory distress occurs within first 6 hours.
HMD occurs in pre-term neonate.