Learning objectives
- •
Identify indications and contraindications to operative vaginal delivery
- •
Identify the flexion point and apply proper technique to vacuum-assisted vaginal delivery
- •
Describe and apply proper technique to forceps-assisted vaginal delivery
- •
List potential maternal and neonatal complications of operative vaginal delivery
Operative vaginal delivery is a delivery in which the operator uses forceps or a vacuum to facilitate the delivery of the fetus. When successful, operative vaginal delivery avoids cesarean delivery and all the associated morbidities and complications. It should be performed only by experienced obstetricians and care providers with privileges.
Indications for Operative Vaginal Delivery
- •
Prolonged second stage of labor
- •
Suspicion of immediate or potential fetal compromise
- •
Shortening of the second stage of labor for maternal benefit (e.g., cardiac, neurologic, or lung disease)
Contraindications to Operative Vaginal Delivery
- •
Unengaged head
- •
Unknown position of fetal head
- •
Live fetus with known or strongly suspected bone demineralization disorder or bleeding disorder
- •
Brow or face presentation
- •
Suspected fetal–pelvic disproportion
Vacuum-Assisted Vaginal Delivery
Vacuum-assisted delivery (Fig. 10.1) has risen in popularity largely due to a belief that it is easier to learn. It is generally less traumatic for the mother than forceps-assisted delivery. However, it still carries a risk of neonatal complications and should only be used by skilled providers. It is more likely to fail than forceps-assisted delivery. Use of vacuum under 34 weeks of gestation or in small fetuses is discouraged .
Vacuum Extraction Technique
- •
Obtain maternal consent to proceed with operative vaginal delivery
- •
Confirm the bladder is empty, the cervix is fully dilated, and fetal position is known
- •
Test for proper function of the vacuum equipment
- •
Identify the flexion point 3 cm anterior to the posterior fontanelle and centered over the sagittal suture ( Fig. 10.2 )
Fig. 10.2
The center of the vacuum cup should be placed at flexion point, which is 3 cm anterior to the posterior fontanelle. In most babies, this will mean the edge of the cup will be 3 cm posterior to the anterior fontanelle.
- •
Place the vacuum cup over the flexion point while ensuring that there is no maternal tissue under the cup
- •
Initiate vacuum pressure according to the manufacturer instructions (typically 450–600 mmHg) ( Fig. 10.3 )
Fig. 10.3
The vacuum pressure is adjusted so the pressure is in the “green zone” as labeled by the manufacturer, typically 450–600 mmHg.
- •
With each contraction, apply traction in the direction of the pelvic curvature ( Fig. 10.4 ). Do NOT employ rocking motions or rotational force
Fig. 10.4
Traction is applied in a J-like motion following the direction of the pelvic curvature.
- •
Consider abandoning attempt at operative vaginal delivery if any of the following occurs :
- •
No progress in one to two pulls
- •
Delivery is not imminent after four contractions and/or 20 minutes
- •
There are three pop-offs without an obvious cause
- •
Forceps-Assisted Vaginal Delivery
Forceps delivery is more likely than vacuum to result in a successful vaginal birth. It allows the operator to rotate the fetus. However, it is more likely to result in third and fourth perineal tears than is vacuum-assisted delivery. “Baby” Elliot and “baby” Simpson forceps have been used for small fetuses. We suggest avoiding forceps for fetuses under 1500 g of weight. We suggest becoming familiar with one type of forceps. We prefer the Simpson forceps ( Fig. 10.5 ).
Types of Forceps Deliveries
- •
Outlet forceps
- •
Scalp is visible at the introitus without separating the labia
- •
Fetal skull has reached the pelvic floor
- •
Fetal head is at or on perineum
- •
Sagittal suture is in anteroposterior diameter or right or left occiput anterior or posterior position
- •
Rotation does not exceed 45°
- •
- •
Low forceps
- •
Leading point at the fetal skull is at station +2 cm or more and not on the pelvic floor
- •
If rotation is greater than 45°, classified as “low forceps with rotation”
- •
- •
Midforceps
- •
Station is above +2 cm but head is engaged
- •
Forceps Delivery Technique
- •
Obtain maternal consent to proceed with operative vaginal delivery
- •
Confirm the bladder is empty, the cervix is fully dilated, and fetal position can be assessed
- •
Perform a “phantom application” with the forceps blades. Visualize how the blades would appear when correctly applied. Begin with a delicate hold of the left blade in the left hand. Then, apply the right blade on top of the left and lock together
- •
Apply forceps to fetal head between contractions. Again, apply the left blade followed by the right blade and ensure they are locked in place ( Fig. 10.6 )
