Many women who have had a previous cesarean delivery (c-section) would like to consider a vaginal birth for other babies. If you have delivered one or two babies by c-section in the past, you may have two options for delivery with this pregnancy:
- Trial of Labor After Cesarean (TOLAC), with the goal of a vaginal delivery.
- Elective repeat cesarean delivery.
Women & Infants and Care New England are providing you with information about both types of delivery to help you make your decision, along with your health care provider. This information will also be helpful before you are asked to sign an obstetrical consent form at the Care New England hospital (Kent or Women & Infants) at which you will be delivering your baby.
How successful is a Trial of Labor After Cesarean (TOLAC)?
Between 60 and 80 percent of women who attempt a trial of labor after a cesarean delivery will be able to deliver vaginally. There are tools that will allow your doctor or midwife to look at your individual history and try to predict your chance for a successful vaginal delivery.
Some factors that may increase your chances of a successful TOLAC:
- Women with a prior vaginal delivery.
- Women who begin labor on their own.
- Women who had their first cesarean section for reasons that are not likely to happen again (i.e. the baby was in the breech position or the baby was not tolerating labor)
Some factors that may decrease your chances of a successful TOLAC:
- Increased age of the mother.
- High birth weight of previous baby(ies).
- Women who are overweight.
- A pregnancy that continues beyond the due date.
- Short time interval between pregnancies (less than 18 months).
Who is a candidate for a TOLAC?
The type of incision in the uterus (womb, not the skin) is an important factor in deciding who is a candidate for TOLAC.
A sideways, or transverse, incision in the lower part of the uterus forms a strong scar with a low risk of rupture in future pregnancies. This is the most common type of cesarean delivery.
Women with an up and down, or vertical incision in the lower part of the uterus can be considered for TOLAC, but may have a higher risk of scar rupture.
Women with a "classical" incision, or a vertical incision in the upper part of the uterus, are not candidates for TOLAC, as the risk of uterine rupture is considered to be too high.
Most women who have had one previous cesarean delivery with a transverse incision are candidates for a TOLAC. The American College of Obstetrics and Gynecology (ACOG) recently affirmed that women with two prior cesarean deliveries and women with a twin pregnancy and one prior cesarean delivery can consider TOLAC, but may have a higher risk of uterine rupture. You should discuss your options with your own obstetrical provider
Your doctor or midwife will review your records to determine what type of incision you had with your previous c-section(s). If your records are not available, your clinician will not be able to tell your type of incision, and you will both decide on your best option for delivery.
Which delivery option has the least risk?
- The fewest complications occur with a successful trial of labor after cesarean and vaginal delivery, also called a vaginal birth after cesarean (VBAC).
- The risk of complications with a scheduled or elective repeat cesarean delivery is greater than with a successful TOLAC and VBAC.
The highest risk for complications is with patients who have an unsuccessful TOLAC and emergency cesarean delivery.
What are the benefits of a TOLAC?
If a TOLAC results in a vaginal birth, the patient typically has the best outcome.
These improved outcomes include:
- Faster recovery time.
- Shorter hospital stay.
- Less chance of a blood transfusion.
- Lower risk of infection.
- Avoiding major surgery.
What are the risks of a TOLAC?
Uterine rupture is a risk with a trial of labor. The risk of uterine rupture with a previous low transverse (sideways) cesarean delivery is less than 1percent.
If a uterine rupture does occur, an emergency cesarean delivery will be needed.
The baby may be seriously injured or could die if a uterine rupture occurs.
Occasionally, the uterus cannot be repaired after a rupture and hysterectomy (removal of the uterus) is required. The risk of uterine rupture is increased when labor is induced, rather than when a woman goes into labor naturally.
Other risks to the patient with uterine rupture include:
- Blood transfusion.
- Injury to internal organs and structures (bowel, bladder and urinary tract).
- Blood clotting problems.
- Very rarely, patient death due to complications.
If a trial of labor is not successful, you will need to undergo a repeat cesarean delivery and will have more risk of complications than with a planned or elective repeat cesarean delivery. These risks include a greater chance of blood transfusion and infection.
Who should NOT attempt a TOLAC?
For some women, the risks of TOLAC exceed the benefits. These women include those with:
- Previous classical cesarean delivery, due to the type of incision.
- Some types of previous uterine surgery including the removal of fibroids.
- More than two consecutive cesarean deliveries with no prior vaginal deliveries.
- Prior uterine rupture or dehiscence (separation of scar).
- Too small a pelvis.
- Medical or obstetrical problems that prevent vaginal delivery.
What are the benefits and risks of a scheduled or elective repeat cesarean delivery?
Patients who undergo a scheduled or elective repeat cesarean delivery avoid the risks of an unsuccessful trial of labor. They can also select a date for their delivery.
The outcomes of scheduled or elective repeat cesarean delivery are more complicated than with successful TOLAC and may include:
- Higher rate of infection than with vaginal birth.
- Greater blood loss and higher risk of transfusion.
- Rare injury to bowel or urinary tract.
- Increased risk of problems with the placenta with future pregnancies.
- Rare need for hysterectomy (removal of the uterus).
All of these risks are higher the more cesarean deliveries you have.
In addition, there is an increased risk of problems with the placenta with each cesarean delivery.
If you have further questions, please speak with your health care provider.
For most patients with a prior cesarean delivery, a Trial of Labor after Cesarean (TOLAC) is a reasonable option to consider. Once your obstetrical provider has decided that you are an appropriate candidate for TOLAC, the choice is up to you. You also have the option of an elective repeat cesarean delivery, and your provider will help you make this decision.
If you decide on TOLAC, you can change your mind and have a cesarean delivery. Your doctor or midwife may also decide that it is unsafe for you to continue your trial of labor and perform a repeat cesarean delivery.