Assisted or operative vaginal birth refers to the use of a vacuum or forceps to achieve a vaginal birth in the second stage of labor for fetal or maternal indications. When deciding whether to perform an assisted vaginal birth (AVB), considerations must include indications and contraindications to the procedure, timing and choice of instrument, the maternal or fetal risks of using either instrument, the urgency of the need to expedite delivery, the experience and skills of the birth attendant, and the risks associated with the alternative choice of cesarean section in the second stage of labor. Regardless of the instrument used, the indications for AVB are the same. The operator should assess the safety and likelihood of success by considering the estimated fetal weight, adequacy of the maternal pelvis, fetal station, fetal position, and adequacy of anesthesia prior to use of either forceps or the vacuum. AVB should only be attempted if there is a reasonable chance of success, and a backup plan should be in place in case the attempt is not successful. Forceps or vacuum extraction is contraindicated if the fetal head is not engaged in the pelvis or if the fetal position cannot be determined.
RATES OF ASSISTED VAGINAL BIRTH
The rate of AVB in North America has decreased over time, while the rates of primary cesarean birth have been increasing. The rates of vacuum-assisted vaginal birth are higher than the rates of forceps-assisted vaginal birth. Reasons for declining rates of forceps use may include increased litigation, unfavorable publicity regarding forceps, decreasing family size, and improved safety of cesarean section. The decrease in forceps use and the increase in cesarean section rates may also be secondary to a decrease in operator skills required to perform a forceps delivery because obstetric trainees now receive less exposure to forceps training.
Many international colleges and societies have advocated for increased use of AVB in order to reduce the increasing rate of cesarean births. The current challenge for promoting AVB is ensuring adequate health care provider training and skills. It is widely accepted that obstetrical trainees should receive appropriate comprehensive training in AVB and deemed competent prior to independent practice. This maintains a high standard of care and the highly skilled Art of Obstetrics in the next generation of care providers.
Whether to use forceps or a vacuum extractor (and the specific instrument) will depend on the clinical circumstances, provider preference based on experience and training, and the patient’s choice. Informed consent is an essential part of an AVB. The indications for vacuum and forceps are the same, although it is believed that vacuum extraction is easier to learn. Vacuum may be preferred when asynclitism prevents proper forceps placement, while forceps provide a more secure application and are used to rotate the fetal head to the occipitoanterior (OA) or occipitoposterior ...