Fetal cranial injuries related to delivery with the Malmström vacuum extractor.

The literature regarding the propensity of the vacuum extractor to cause fetal cranial injuries is reviewed. Eighteen subaponeurotic hemorrhages occurred in 14,276 vacuum extractions (VE). Scalp abrasion or laceration occurred in 12.6%, cephalohematoma in 6%, and intracranial hemorrhage in 0.35%. Assessments of early and late manifestations of neurologic damage indicate little difference between VE deliveries and spontaneous deliveries. An uncorrected perinatal mortality rate of 25.8 per thousand is tabulated, which reduced to 15 per thousand when corrected for deaths not related to the mode of delivery. Scalp anatomy and the forces exerted on it with vacuum extraction are examined, and suggestions to minimize scalp injuries are offered.