Effect of mode of delivery in nulliparous women on neonatal intracranial injury.

Background: Infants delivered by vacuum extraction or other operative techn iques may be more likely to sustain major injuries than those delivered spo ntaneously, but the extent of the risk is unknown. Methods: From a California data base, we identified 583,340 live-born singl eton infants born to nulliparous women between 1992 and 1994 and weighing b etween 2500 and 4000 g. One third of the infants were delivered by operativ e techniques. We evaluated the relation between the mode of delivery and mo rbidity in the infants. Results: Intracranial hemorrhage occurred in 1 of 860 infants delivered by vacuum extraction, 1 of 664 delivered with the use of forceps, 1 of 907 del ivered by cesarean section during labor, 1 of 2750 delivered by cesarean se ction with no labor, and 1 of 1900 delivered spontaneously. As compared wit h the infants delivered spontaneously, those delivered by vacuum extraction had a significantly higher rate of subdural or cerebral hemorrhage (odds r atio, 2.7; 95 percent confidence interval, 1.9 to 3.9), as did the infants delivered with the use of forceps (odds ratio, 3.4; 95 percent confidence i nterval, 1.9 to 5.9) or cesarean section during labor (odds ratio, 2.5; 95 percent confidence interval, 1.8 to 3.4), but the rate of subdural or cereb ral hemorrhage associated with vacuum extraction did not differ significant ly from that associated with forceps use (odds ratio for the comparison wit h vacuum extraction, 1.2; 95 percent confidence interval, 0.7 to 2.2) or ce sarean section during labor (odds ratio, 0.9; 95 percent confidence interva l, 0.6 to 1.4). Conclusions: The rate of intracranial hemorrhage is higher among infants de livered by vacuum extraction, forceps, or cesarean section during labor tha n among infants delivered spontaneously, but the rate among infants deliver ed by cesarean section before labor is not higher, suggesting that the comm on risk factor for hemorrhage is abnormal labor. (N Engl J Med 1999;341:170 9-14.) (C) 1999, Massachusetts Medical Society.