Subcutaneous emphysema, pneumomediastinum, and pneumothorax in labor and delivery.

Hamman's syndrome occurs rarely in the setting of labor and delivery. In this report 187 cases of Hamman's syndrome, with and without objective evidence of pneumothorax, are summarized and the literature reviewed. Most of the women were primiparous, and first and second stages of labor were of normal duration (18.3 and 4.1 hour, respectively). Average fetal size (7 pounds, 14 ounces) was also found to be within normal limits. Signs, symptoms, and pathophysiology are reviewed and treatment discussed.