Type of uterine incision—How your doctor opened your uterus during your prior C-section may influence your risk for uterine rupture (the uterine scar tearing during VBAC labor). VBAC is not recommended for women who have a “classical” incision (vertical cut through the upper part of the uterus), “T-shaped,” or “J-shaped” incisions. The scars from these incisions are more likely to tear.
Reason for prior C-section—The chances of having a successful VBAC are lower for women who had a prior C-section for a reason that could recur with their next labor and delivery. Reasons include a difficult labor and the cervix not opening fully.
Number of prior C-sections—A higher number of prior C-section deliveries decreases the likelihood for a successful VBAC because the uterine wall has been weakened.
Baby’s size and gestational age—Babies weighing more than 8.8 pounds (4,000 grams) or more than 40 weeks gestation are less likely to be delivered successfully by VBAC.
or augmentation—Some labor-inducing drugs can increase the risk for uterine rupture. Because of this, your doctor may advise against a VBAC if you require these drugs.
Pregnancy complications—Complications may require a C-section delivery.
Birthing complications—Problems, such as the cervix not opening fully, may result in a C-section. Also, a VBAC may not be possible if your baby’s head is too large to fit through your pelvis.
Baby’s position—A breech baby (feet or buttocks entering the birth canal) or transverse baby (lying sideways across the pelvis) cannot be delivered vaginally.
Multiples—Twins may be delivered vaginally if both babies are positioned head-first for delivery. However twin births tend to be more complicated than singleton births. Because of this, many women and their doctors choose a C-section delivery. Women carrying triplets or more typically have a C-section.
Mother’s health—Conditions (eg, diabetes, heart disease,
high blood pressure
) may make a vaginal delivery higher risk for complications for you and your baby. Also, women who are over 40 are less likely to have a successful vaginal birth.
What to Expect
Prior to Procedure
VBAC is managed just like any other pregnancy with an anticipated vaginal delivery.
The same pain medications are available for VBAC as for a typical vaginal delivery. Most women opt for an
epidural or spinal block
Description of the Procedure
Once labor begins your doctor will want you to come to the hospital right away. You and your baby will be monitored closely throughout labor and delivery to make sure that the baby’s heart rate is normal and that labor is progressing normally. If complications arise, your doctor may quickly suggest a C-section, rather than treat the problem or wait for the problem to correct itself. This is to avoid the risk of uterine rupture.
Recovery following VBAC is the same as that for a regular vaginal delivery.
How Long Will It Take?
This is extremely variable. The average length of time for a first baby (and its placenta) to be born, once a mother is in active labor, is 12 hours.
Will It Hurt?
Yes, but you can learn various techniques to try to lessen the pain. You should learn as much as possible about childbirth ahead of time so that you can decide if you want to use an epidural or other pain medication.
Although uncommon, possible complications of a VBAC delivery include the following:
Unsuccessful VBAC—Between 20%-40% of women attempting VBAC require a repeat C-section. Most often this is due to fetal distress during labor or delivery or problems with contractions.
Stretching of prior uterine scar—Sometimes the prior C-section uterine scar may stretch during labor. This typically does not pose problems for the mother or baby. The scar heals on its own.
Emotional stress—Although the need for a C-section is out of your control, you may feel responsible for the outcome.
Endometritis—Infection of the membrane lining your uterus is more likely to occur following a failed VBAC than with a planned C-section.
Uterine rupture—This rare, but life-threatening condition occurs when the uterus tears along the prior C-section scar. This is due to insufficient healing of the prior uterine incision. An emergency C-section is performed in this situation.
Average Hospital Stay
Postoperative care is the same as for a typical vaginal delivery.
Call Your Doctor If Any of the Following Occurs
After you leave the hospital, call your doctor if any of the following occurs:
Fever of 100.4°F
Soak more than one sanitary napkin an hour or if the bleeding level increases
The American College of Obstetricians and Gynecologists. Vaginal birth after previous cesarean section.
Landon MB. Maternal and perinatal outcomes associated with a trial of labor after prior Cesarean delivery.
N Engl J Med
Trial of labor after cesarean (TOLAC), formerly trial of labor versus elective repeat cesarean section for the women with a previous cesarean section. The American Academy of Family Physicians website. Available at
. Accessed August 31, 2005.
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a