VBAC after two C-sections: candidacy and risk

What does the evidence say about VBAC after two C-sections during pregnancy?

1. NICHD states that VBAC may be appropriate for some patients with two previous low-transverse uterine incisions. Its page emphasizes early discussion and referral to a facility that can support VBAC when medically appropriate. 1
2. ACOG explains that the uterine incision, not the visible skin scar, determines scar type and advises obtaining prior operative records. A low-transverse incision carries the lowest rupture risk, while a prior classical or high vertical incision usually rules out TOLAC. 2
3. A systematic review of 20 observational studies reported pooled VBAC-after-two success of 71.1% and uterine rupture of 1.36%. There were no randomized trials, neonatal data were limited, and selection practices varied, so these are counseling estimates rather than personal predictions. 3
4. A prospective multicenter observational study included 975 trials of labor after multiple cesareans and 16,915 after one. Rupture was 0.9% versus 0.7%, a nonsignificant difference, while transfusion and hysterectomy were more frequent after multiple scars; the multiple-scar group was not limited to exactly two. 4
5. An NCBI clinical review says operative records, prior vaginal birth, reason for prior cesareans, current presentation, and facility capacity influence candidacy and success. It reports that most U.S. practitioners consider up to two prior cesareans potentially eligible when scars and other factors are suitable. 5

How this changes over time

• Request both prior operative reports early. The skin scar does not reveal the uterine incision, and records may identify a classical, T-shaped, or other upper-uterine incision that changes candidacy.
• Review prior birth reasons, any vaginal birth, placenta location, fetal presentation, medical conditions, and the planned hospital's emergency cesarean capability. If the local hospital cannot support TOLAC, referral takes time.
• Finalize a plan for spontaneous labor, induction questions, when to come in, and circumstances that would prompt repeat cesarean. During labor, continuous fetal monitoring and immediate access to surgical, anesthesia, and newborn teams are important.