Clinical assessment of the Kobayashi vacuum extractor.

Four hundred and thirty-one vacuum extraction deliveries were reviewed during a five-year period from 1978 to 1983. All cases involved the use of the Kobayashi silastic cup vacuum extractor with nine participating obstetricians performing the procedures. Specific attention was directed toward maternal and fetal morbidity associated with the use of the silastic cup extractor. No maternal or fetal deaths occurred. Vaginal and cervical lacerations accounted for a 4% maternal morbidity rate. Seventy-five percent of the infants had Apgar scores greater than 7 at one minute, and 97% had scores greater than 7 at five minutes. Fetal morbidity was impressively low, with a cephalohematoma rate of 6% and only two instances of major fetal cranial hemorrhages. In comparison with the reported morbidity sited by other authors using the metal cup extractor, less fetal scalp trauma may be anticipated with the judicious use of the Kobayashi silastic cup vacuum extractor.