Which respiratory disorder occurs in term and near-term infants due to delayed clearance of fetal lung fluid?

• A. Transient Tachypnea of the newborn (TTN)
• B. Respiratory Distress Syndrome
• C. Pulmonary hypertension of the newborn
• D. Meconium aspiration syndrome

Answer: (A)

The main idea being tested is that transient tachypnea of the newborn occurs when there is delayed clearance of fetal lung fluid in term and near-term infants. After birth, fluid that filled the fetal lungs is normally removed quickly into the interstitium and lymphatics, aided by hormonal and mechanical changes that occur during labor. When this clearance is delayed—often seen after cesarean delivery without labor—the lungs retain fluid, which reduces lung compliance and leads to rapid breathing and mild respiratory distress soon after birth.

Clinically, you’ll see tachypnea and signs of mild distress within the first hours of life, and the chest x-ray typically shows hyperinflation with prominent markings or mild interstitial edema, reflecting retained fluid rather than surfactant deficiency. The course is typically self-limited, improving with supportive care such as supplemental oxygen or nasal CPAP as needed, often resolving within 24–72 hours.

Other respiratory conditions have different roots: surfactant deficiency causing respiratory distress syndrome is more common in preterm infants; meconium aspiration involves inhalation of meconium and often occurs in post-term infants with airway irritation; pulmonary hypertension of the newborn has a distinct hemodynamic basis with persistent high pulmonary pressures. The description here—term or near-term infants with delayed fluid clearance leading to tachypnea—fits transient tachypnea of the newborn precisely.