Soft cup vacuum extraction: a comparison of outlet delivery.

One hundred eighteen nulliparous patients delivered under conduction anesthesia who met the standard criteria for low forceps delivery were randomly assigned to one of three groups to be delivered by low Tucker-McLane forceps, Silastic vacuum extraction system, or Mityvac vacuum extractor. Significant maternal soft tissue trauma was identified in 48.9% of the forceps group, 36.1% of the Silastic group, and 21.6% of the Mityvac group. Superficial fetal scalp changes were found in 71% of the forceps group, 44% of the Silastic group, and 46% of the Mityvac group. Of these, cephalhematomatas were noted in 2.2% of the forceps group, 13.9% of the Silastic group, and 16.2% of the Mityvac group. All three instruments were considered effective outlet delivery instruments.