According to childbirthconnection.org, almost all care providers, including those who usually encourage VBAC, would strongly recommend planned cesarean in the following situations:
- certain uterine scars from a cesarean that aren't the usual horizontal cut made at the bottom of the uterus (low transverse scar): In these rare situations, the concern is that the scar on the uterus may be weaker and more likely to give way (rupture) and cause serious problems than the usual cesarean scar.
- a high cesarean scar that runs up-and-down (vertical or "classical" uterine incision): a vertical incision may have been used if you had a placenta that grew over the opening to your uterus (placenta previa), for some urgent cesareans, or in some cases previous baby was in a buttocks- or feet-first (breech) position. (It is possible to have a low horizontal scar on your skin but a vertical cut on your uterus.)
- inverted T- or J-shaped incision
- mother had previous uterine surgery for gynecologic problems, such as for removal of fibroid tumors
- uterine scar opened and caused problems in a prior labor: The key point here is that the scar has caused problems before. Many times, scar openings are small, harmless "windows" (dehiscences). These windows are not thought to have any ill effects in future labors.
- uterus does not have the usual pear shape: Examples of this are a heart-shaped (bi-cornate) uterus or a uterus that is partly divided down the middle (septate uterus).
- ultrasound in late pregnancy finds that the area of the scarred uterus is unusually thin: There may be a concern if the scar is 2.5 millimeters thick (about the height of 2 stacked dimes) or less.