Respiratory Distress: Relation to Prematurity and Other Factors in Newborn Monkeys.

A respiratory distress syndrome resembling that seen in human infants was encountered in 4 out of 90 rhesus monkey infants after uncomplicated births. These were nonviable immature infants weighing less than 350 grams. A much higher incidence of respiratory distress was observed in those whose births were complicated by experimental procedures, mainly asphyxiation. Thirty-four out of 68 infants developed the syndrome, the incidence being greatest among the least mature.