Which stage of fetal lung development involves the formation of trachea and separation from the esophagus?

The formation of the trachea and its separation from the esophagus occurs during the embryonic stage of fetal development. This stage, which takes place from the third to the seventh week of gestation, is characterized by significant developmental milestones in the formation of the respiratory system.

During the embryonic stage, the lung buds emerge from the foregut and begin to branch into the trachea and bronchial tree. This branching process is essential for creating the structures necessary for effective respiration after birth. The separation of the trachea from the esophagus occurs due to the development of the tracheoesophageal septum, which is crucial for normal respiratory function and ensuring that air and food travel through their respective pathways.

The subsequent stages of lung development, such as the pseudoglandular, canalicular, and saccular stages, involve further maturation of the lung structures, including the development of alveoli and the establishment of respiratory function, but the foundational separation of the trachea from the esophagus is attributed to the embryonic stage.