Which condition is characterized by respiratory distress onset within 1-2 hours after birth?

Transient Tachypnea of the Newborn (TTN) is characterized by respiratory distress that typically begins within the first 1-2 hours following birth. This condition is often observed in newborns who have experienced a rapid delivery or those that were born via cesarean section without preceding labor. The respiratory distress is thought to result from retained fluid in the lungs that has not been adequately cleared, leading to symptoms such as increased respiratory rate, nasal flaring, and grunting.

The timing of the onset of respiratory distress is a critical factor in diagnosing TTN. The relatively early onset, along with the typical resolution of symptoms within roughly 72 hours, helps differentiate this condition from others like pneumonia or respiratory distress syndrome, which either present later or have different underlying pathophysiologies. Meconium Aspiration Syndrome can also lead to rapid respiratory distress, but it's typically associated with complications during labor or the presence of meconium-stained amniotic fluid. In contrast, Respiratory Distress Syndrome usually presents within the first few hours of life due to surfactant deficiency and relates more to prematurity.

Thus, the rapid onset of respiratory distress shortly after birth, coupled with the clinical presentation and typical course, solidly identifies Transient