To describe the presentation and outcome of infants who develop subgaleal hematoma (SGH), we compared perinatal factors, clinical and head imaging findings, and outcome in a cohort (N = 34) of all infants admitted to Saint Louis Children's Hospital neonatal intensive care unit with SGH from January 1991 to June 2003. All except three of the infants admitted with SGH had instrumental deliveries (31 of 34; 91.2%): 21 vacuum, eight vacuum followed by forceps, two forceps). There was also a high frequency of occurrence of associated intracranial hemorrhage (17 of 34; 50%: subarachnoid hemorrhage, n = 4; intraventricular hemorrhage, n = 4; intraparenchymal hemorrhage, n = 4; subdural hemorrhage, n = 11), and skull fracture (six of 34; 19.4%; three of six [50%] of them depressed fractures). There was mortality associated with SGH (four of 34, 11.8%); those who died had significant volume loss with anemia, coagulopathy, and shock requiring large volumes of blood and blood products transfusions. The presence of ICH did not correlate with the severity of SGH or mortality, but the severity of SGH correlates with mortality. Minor neurological abnormalities were noted in only four infants at discharge. In conclusion, SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by instrumentation (vacuum and/or forceps). Severe hypovolemia and coagulopathy, but not intracranial hemorrhage, were the most commonly associated clinical problems with mortality. ICH does not correlate with severity of SGH. A brain computed tomography or magnetic resonance imaging should be considered in evaluating a clinically symptomatic SGH. There is associated mortality in severe cases but short-term outcome in survivors is good.