Results: Pneumothorax of patient group occurred more frequently in right side than pneumothorax with control group(76.9% vs 60.0%). Gestational age(37+5±1 vs.38+6±1weeks) and initial pneumothorax finding time(14.1±30.7 vs.24.9±20.5hr) of patient group were earlier than control group. Otherwise, there were similar findings between groups.