Once you have a cesection why must you have another one!?

You don't: Depending on the type of uterine incision (not the skin incision), some women are ok for a trial of labor with a second pregnancy. The main risk is uterine rupture, which is rare but serious, as it can threaten the baby's life or yours. Another limiting factor is that your doctor must be closely available during labor, which can stop some providers from offering vbac.