Use of Sequential Vacuum, Forceps Raises Injury Risk.

Hemorrhages, nerve injury, lacerations seen.

RENO, NEV. -- The risks of both maternal and fetal injury are increased with the sequential use of vacuum extraction and forceps for assisted vaginal delivery, Dr. Carolyn Gardella reported at the annual meeting of the Society for Maternal-Fetal Medicine.

A retrospective, population based cohort study of more than 33,000 births using Washington state birth certificate data found increased risks of intracranial hemorrhage, facial nerve injury, maternal lacerations, and postpartum hemorrhage with combined assisted vaginal deliveries.

The risk of maternal morbidity associated with sequential use approximated the sum of the individual risks of vacuum extraction or forceps used alone, Dr. Gardella explained.

But the risk of neonatal morbidity was greater than the sum of individual risks for either approach used alone, "suggesting a synergistic interaction effect of sequential use of these instruments," she said.

The study included 3,732 vacuum-assisted deliveries, 3,723 forceps-assisted deliveries, and 3,735 deliveries in which both were used sequentially.

A control group included 11,214 nonassisted deliveries, 9,763 of which were vaginal and 1,451 of which were by cesarean section.