Operative Vaginal Delivery

Operative vaginal delivery involves application of forceps or a vacuum extractor to the fetal head to assist during the second stage of labor and facilitate delivery.

Indications for forceps delivery and vacuum extraction are essentially the same:

• Prolonged second stage of labor (from full cervical dilation until delivery of the fetus)

• Suspicion of fetal compromise (eg, abnormal heart rate pattern)

• Need to shorten the second stage for maternal benefit—eg, if maternal cardiac dysfunction (eg, left-to-right shunting) or neurologic disorders (eg, spinal cord trauma) contraindicate pushing or maternal exhaustion prevents effective pushing

A prolonged second stage is defined as follows (1):

• In nulliparous women: Lack of continuing progress for 4 hours with a regional anesthetic or 3 hours without a regional anesthetic

• In multiparous women: Lack of continuing progress for 3 hours with a regional anesthetic or 2 hours without a regional anesthetic

Choice of device depends largely on user preference and operator experience and varies greatly. These procedures are used when the station of the fetal head is low (2 cm below the maternal ischial spines [station +2] or lower); then, minimal traction or rotation is required to deliver the head.

Before starting an operative vaginal delivery, the clinician should do the following:

• Confirm complete cervical dilation

• Confirm an engaged fetal vertex at station +2 or lower

• Confirm rupture of membranes

• Confirm that fetal position is compatible with operative vaginal delivery

• Drain the maternal bladder

• Clinically assess pelvic dimensions (clinical pelvimetry) to determine whether the pelvis is adequate

Also required are informed consent, adequate support and personnel, and adequate analgesia or anesthesia. Neonatal care providers should be alerted to the mode of delivery so they can be ready to treat any neonatal complications.

Contraindications include unengaged fetal head, unknown fetal position, and certain fetal disorders such as hemophilia. Vacuum extraction is typically considered contraindicated in preterm pregnancies of < 34 weeks because risk of intraventricular hemorrhage is increased.

Major complications are maternal and fetal injuries and hemorrhage, particularly if the operator is inexperienced or if candidates are not appropriately chosen. Significant perineal trauma and neonatal bruising are more common with forceps delivery. Shoulder dystocia, cephalohematoma, jaundice, and retinal bleeding are more common with vacuum-assisted delivery, although the rates remain low. If operative vaginal delivery results in third- or fourth-degree perineal lacerations, prophylactic antibiotics should be considered before the lacerations are repaired (2, 3); antibiotics may reduce the risk of wound complications.