What causes transient tachypnea of the newborn?

• A. Infection during birth
• B. Delay in clearance of fetal lung fluid
• C. Maternal diabetes
• D. Elective cesarean section

Answer: (B)

Transient tachypnea of the newborn (TTN) is primarily caused by a delay in the clearance of fetal lung fluid. During labor and delivery, especially in vaginal births, the newborn is exposed to significant mechanical stress, which helps in the absorption and expulsion of this fluid from the lungs. In some cases, particularly with a lack of these stresses, such as in elective cesarean deliveries or other factors delaying the normal fluid clearance process, residual fluid can remain in the lungs.

As a result, this fluid creates a temporary obstruction in the airways, leading to difficulty in breathing and an increased respiratory rate, which is characteristic of TTN. This condition typically resolves within a few days as the newborn's lungs clear the remaining fluid on their own.

While other factors like infections or maternal conditions may contribute to respiratory issues in newborns, they do not directly cause TTN as the primary mechanism involves the lung fluid clearance process.