Risks of VBAC
A cesarean delivery is major surgery, with all of the associated risks. When successful, VBAC is safer than c-section. VBAC is associated with a small risk of uterine rupture, but it is considered to be a safe option for some by the American College of Obstetricians and Gynecologists (ACOG).
A uterine rupture is a surgical emergency that occurs during labor and sometimes before labor starts. The uterine wall tears at the site of a prior surgical incision and sometimes tears as a result of weak uterine muscle tissue (caused by multiple pregnancies or infection). The infant may be expelled from the uterus into the mother's abdominal cavity, which can result in infant brain damage or death.
The incidence of uterine rupture with VBAC in a mother who has had a low transverse incision is approximately 0.2–1.5 percent.
Accompanying the elevated risk of uterine rupture is an increased risk for hysterectomy (surgical removal of the uterus). However, most cases are managed by controlling the bleeding and repairing the tear surgically. Also, there are indications that a failed attempt at VBAC followed by a c-section increases the rate of infection in infants and mothers.
There is no conclusive evidence that labor induced with pitocin or prostaglandin gel creates a risk in VBAC. However, some studies indicate that the use of prostaglandin gel in VBAC cases may increase the risk of uterine rupture, hemorrhaging, and hysterectomy in the mother and of subsequent fetal distress and infant death.
Benefits of VBAC
Some of the benefits of VBAC are as follows:
- Epidural analgesia
- Fewer medical risks to mother and baby
- Less blood loss and fewer blood transfusions
- Less risk for infection for mother and infant
- Lower cost
- Shorter post-delivery recovery time for the mother
Prognosis of VBAC
The success rate for VBAC is approximately 60–80 percent and can be higher if the patient had a vaginal delivery prior to c-section. In patients who had a c-section performed because of dystocia (abnormal or difficult labor), the success rate is lower. The most common causes of difficult labor include:
- Cephalopelvic disproportion or "CPD" (the infant is too large for the pelvis)
- Failure to progress (contractions are not productive; cervix does not dilate; labor lasts too long)