VBAC

Trial of Labor and Vaginal Birth After Cesarean in Fort Worth, TX

For women who desire a vaginal delivery after a prior cesarean section, a trial of labor after cesarean section (TOLAC) provides the possibility of achieving the goal of a vaginal birth (VBAC).

 

Benefits

If successful, a vaginal delivery is associated with lower rates of hemorrhage, infection, and shorter recovery periods. In addition, women may avoid potential consequences of multiple cesarean sections, such as, bowel/bladder injury, transfusions, infection, hysterectomy, and abnormal placentation such as placenta previa or placenta accreta.

Approximately 60-75% of women who undergo a TOLAC are successful in achieving a VBAC. Success rates are significantly influenced when labor is spontaneous and the woman has had a previous vaginal delivery.

 

Risk Factors

Although a TOLAC may be appropriate, several factors my increase the likelihood of a failed trial or labor

1. Risk is increased when the prior cesarean section was for an abnormal labor (dystocia)
2. Decreased success rates when labor is induced, induction of labor also may increase the risk of uterine rupture
3. Advanced gestational age
4. Advanced maternal age
5. Maternal obesity
6. Large fetus (macrosomia)

 

Risk

The primary risk is rupture of the uterus. Secondary risks are complications that occur as a result of the uterine rupture. More specifically, uterine rupture is associated with hemorrhage and the need for transfusions, increase risk of injury to bowel or bladder, and the increased possibility of hysterectomy. Although rare, maternal and/or fetal death can occur.

For most carefully selected patients, the risk of uterine rupture is less than 1 %. A key factor in influencing the risk of uterine rupture is the location of the previous uterine scar (not the same as the skin scar). The risk of rupture is significantly increased if the prior incision is in the more active portion of the uterus called the fundus. This type of scar is usually seen when there was prior uterine surgery for removal of fibroid tumors, for surgery to correct uterine abnormalities, or when the previous cesarean was a classical type incision extending into the more active portion of the uterus.

A TOLAC is a viable option for carefully selected women who desire VBAC. In my practice, I offer the option of a TOLAC/VBAC. I will consider each patient on an individual basis balancing the risk factors vs. the probability of success. In most cases, a prior classical cesarean incision, prior uterine surgery, or when the prior scar is unknown, a TOLAC is contraindicated. Induction of labor increases the risk of uterine rupture, therefore a TOLAC will only be considered when labor occurs spontaneously. Maternal and fetal weight, gestational age, and prior obstetrical history are relative risk factors considered in balancing the risk vs. the probability of success.

If you have had a prior cesarean section and are considering a TOLAC I encourage you to discuss our options.