Trial of Labor After Cesarean Information

A trial of labor after cesarean (TOLAC) is when a woman tries to give birth vaginally after a previous cesarean delivery. When successful, this is called a vaginal birth after cesarean (VBAC). TOLAC may be a safe and appropriate option for you depending on your history and other risk factors.

The chances of a successful VBAC depends on the reason you previously had a cesarean. Women have higher VBAC success rates if their cesarean was due to:

  • A breech (malpresentation) baby.

  • Emergency reasons.

  • Medical factors like hypertension.

Women have lower VBAC success rates if their cesarean was done because they:

  • Did not dilate.

  • Could not push their baby out.

Talk to your caregiver about VBAC benefits, risks, and success rates. Discuss your plans for having more children. After this is done, you and your caregiver can decide whether to attempt TOLAC.

MOST SUCCESSFUL CANDIDATES FOR TOLAC

TOLAC is possible for some women who:

  • Had 1 past horizontal (low transverse) incision during a cesarean.

  • Are carrying twins and had 1 past low transverse incision during a cesarean.

  • Do not have a very large (macrosomic) baby.

  • Do not have a vertical (classical) uterine scar.

  • Are in labor and are less than 41 weeks pregnant.

TOLAC is also supported for women who meet appropriate criteria and:

  • Are under the age of 40.

  • Are tall and have a body mass index (BMI) of less than 30.

  • Are likely carrying a baby that is at an average, or less than average, birth weight.

  • Have an unknown uterine scar.

  • Deliver in a hospital with a proper medical team. This team should be able to handle possible complications such as a uterine rupture.

  • Have thorough counseling about the benefits and risks of TOLAC.

  • Have discussed future pregnancy plans with their caregiver.

  • Plan to have several more pregnancies.

TOLAC may be most appropriate for women who meet the above guidelines and who plan to have more pregnancies. TOLAC is not recommended for home births.

LEAST SUCCESSFUL CANDIDATES FOR TOLAC

TOLAC is least successful for women who:

  • Have an induced labor with an unfavorable cervix. An unfavorable cervix is when the cerix is not dilating sufficiently (among other factors).

  • Have never had a vaginal delivery.

  • Had a past cesarean for failed progress.

  • Had a past cesarean due to abnormal fetal heart rate patterns on the monitor (nonrassuring tracing).

  • Have a macrosomic baby.

  • Are postterm. This means the pregancy has lasted beyond 42 weeks from the first day of the last menstrual period.

There are no high-quality studies comparing the risks and benefits of TOLAC and elective repeat cesarean deliveries.

SUGGESTED BENEFITS OF TOLAC

The benefits of TOLAC include:

  • Having a faster recovery time.

  • Having less pain than with a cesarean.

  • Having the partner involved in the delivery process.

SUGGESTED RISKS OF TOLAC

The highest risk of complications happens to women who attempt a TOLAC and fail. A failed TOLAC results in an unplanned cesarean delivery. Risks related to TOLAC or repeat cesarean surgeries include:

  • Blood loss.

  • Infection.

  • Blood clot.

  • Injury to surrounding tissues or organs.

  • Removal of the uterus (hysterectomy).

  • Potential problems with the placenta (placenta previa, placental acreta) in future pregnancies. 

While very rare, the main concerns with TOLAC are:

  • Rupture of the uterine scar from a past cesarean surgery.

  • Needing an emergency cesarean surgery.

  • Having a bad outcome for the baby (perinatal morbidity).

  • Having closely spaced pregnancies (less than 6 months apart).

ADVANTAGES TO HAVING A REPEAT CESAREAN DELIVERY

  • It is convenient to be able to schedule a cesarean delivery.

  • A woman can easily have surgery to prevent future pregnancies (sterilization) during a cesarean, if desired.

  • There is a lower rate of hysterectomy later in life due to the uterus falling down (pelvic relaxation).

  • The risks associated with TOLAC are not applicable.

FOR MORE INFORMATION

American Congress of Obstetricians and Gynecologists: www.acog.org

American College of Nurse-Midwives: www.midwife.org