ABSITE Practice Exam 2025 – Comprehensive Exam Prep

Congenital diaphragmatic hernia (CDH) primarily occurs due to a defect in the diaphragm allowing abdominal contents to herniate into the thoracic cavity, which can compromise lung development and function. The most common form of CDH is the Bochdalek hernia, which occurs posterolaterally. Notably, left-sided Bochdalek hernias are more frequent than right-sided ones.

In the context of CDH, left-sided Bochdalek hernias account for approximately 85-90% of cases. This predominance is believed to be associated with the developmental aspects of the diaphragm and the positioning of the liver, which provides a partial protective effect on the right side.

Morgagni hernias, while a type of diaphragmatic hernia, are much less common and typically occur anteriorly. Hiatal hernias, another distinct type of hernia, involve the stomach herniating through the diaphragm into the thoracic cavity, but they are not classified under congenital diaphragmatic hernias and thus are not relevant in identifying the most common location for CDH. The right-sided Bochdalek hernia presence is less frequent compared to the left side.

Therefore, the left-sided Bochdalek hernia