With any scar on the uterus, there is a risk that the scar may separate during pregnancy and labor. In some cases, the scar may separate enough to make the uterus rupture. Separation of the scar is more common than having the uterus rupture, and it rarely causes any problems. But rupture of the uterus is a potentially serious complication, especially for the baby.
The risk of uterine rupture depends on the location of the scar. With a horizontal, or side-to-side, scar on the lower part of the uterus, this risk is lower than if the scar is vertical and located on the upper part of the uterus.
Because of this risk, if you have a vertical incision on the upper part of your uterus, your doctor will probably recommend that any children you have in the future be delivered by cesarean section. If you have this type of incision, the consequences of a rupture are usually more serious for both the mother and the baby than a rupture or separation of the scar on the lower part of the uterus.