Why it's done

Common reasons for choosing a trial of labor after cesarean include:

• Impact on future pregnancies. If you're planning to have more children, VBAC might help you avoid the risks of multiple cesarean deliveries, such as placenta previa or placenta accreta.
• Lower risk of surgical complications. Successful VBAC is associated with lower rates of excessive bleeding, infection and blood clotting in one or more of the deep veins in the body (deep vein thrombosis). VBAC also might decrease the risk of surgical removal of the uterus (hysterectomy) and injury to abdominal organs, such as the bladder or bowel.
• Shorter recovery time. You'll have a shorter hospital stay after a VBAC than you would after a repeat C-section. Avoiding surgery will help you resume your normal activities sooner.
• Opportunity for an individualized birth plan. For some women, it's important to experience a vaginal delivery.

You might be a candidate for VBAC if you are:

• Pregnant with one baby, have a history of one or two prior low transverse C-sections, and have no problems that would prevent VBAC
• Pregnant with one baby, have a history of one prior C-section with an unknown type of uterine incision, and have no problems that would prevent VBAC — unless it's suspected that you had a prior high vertical (classical) uterine incision
• Pregnant with twins, have a history of one prior low transverse C-section, and are otherwise a candidate for a twin vaginal delivery

One of the greatest predictors of a successful VBAC is a prior vaginal delivery.

You're not a candidate for VBAC if you have any condition that would prevent vaginal delivery or you have had:

• A prior high vertical (classical) uterine incision
• An unknown type of prior uterine incision and it's suspected that it was a high vertical (classical) incision
• A prior uterine rupture, in which the cesarean scar on the uterus breaks open
• Certain types of prior uterine surgery, such as fibroid removal

Many health care providers won't offer VBAC if you've had more than two prior C-sections or you have a body mass index of 50 or higher at the time of delivery and you've never had a vaginal delivery. VBAC also generally isn't an option if you are pregnant with triplets or higher order multiples.

Factors that decrease the likelihood of VBAC include:

• Stalled labor
• Advanced maternal age
• Pregnancy that continues past 40 weeks
• Body mass index of 40 or higher
• Excessive weight gain during pregnancy
• Preeclampsia
• Previous delivery within 18 months
• History of two or more prior C-sections and no vaginal deliveries
• A need for labor induction when starting with a closed cervix