A cesarean delivery requires two incisions—one in the skin and one in the uterus. Both can be done either vertically or horizontally. Most commonly, both incisions are made horizontally. If a woman has had previous abdominal surgery, the doctor will remove the old scar and use that area for the skin incision. Therefore, if the scar was vertical, the skin incision may not match the uterine incision. The incision in the skin is usually chosen for cosmetic reasons, while the one in the uterus is chosen for medical reasons.
The low transverse skin (Pfannenstiel) incision is made crosswise along the pubic hairline. (See Figure 9.2.) This “bikini cut” is preferred for cosmetic reasons because the scar is barely noticeable. However, the incision takes longer to do and gives the doctor limited space in which to work. Therefore, it is not used in an extreme emergency. On the plus side, discomfort during recovery is less, and the wound heals more quickly. A vertical skin incision is faster to make and gives the doctor more room in which to work. (See Figure 9.3.) Hence, it allows for a quicker delivery in an emergency situation.
The most common uterine incision is the low transverse cervical incision. It is made horizontally in the cervical area. (See Figure 9.4.)Because it is not in the contractile part of the uterus, it forms the strongest scar with the least danger of rupture and fewest postoperative adhesions. The incision is smaller and is thought to heal more quickly. It is the only incision that doctors will accept for a vaginal birth after a cesarean (VBAC).
A classical uterine incision is made vertically in the fundal area and gives the doctor more working room. (See Figure 9.5.) It is done when the baby is large, when the baby is in a transverse lie, when adhesions or scar tissue from previous cesareans are a problem, or when the baby must be delivered immediately. A classical incision forms the weakest scar and heals the slowest. You may not attempt a VBAC with this incision.