What is the minimum thickness of a scarred uterus that poses a risk?
May 08, 2025
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
Under normal circumstances, a scarred uterus is generally considered to be at a higher risk when the thinnest part is less than 3 mm. A scarred uterus refers to the formation of scar tissue beneath the muscular layer of the uterus following a cesarean section, which can significantly reduce the elasticity of the uterine muscle layer. The normal thickness of a scarred uterus is generally 3 mm or more. When the thinnest part of the scarred uterus is less than 3 mm, it is usually considered to be relatively dangerous.
In general, a scarred uterus with a minimum thickness of less than 3 mm is usually considered risky. The detailed explanation is as follows:
A scarred uterus refers to the formation of scar tissue beneath the uterine muscle layer following a cesarean section, which significantly decreases the elasticity of the uterine muscular layer. The normal thickness of a scarred uterus is generally 3 mm or more. When the thinnest part of the scarred uterus is less than 3 mm, it is typically considered dangerous. If the thinnest portion of the scar becomes too thin, the increased pressure on the uterus during pregnancy—especially in the late stages—or during labor can lead to uterine rupture. This poses a severe threat to both the mother and the fetus, potentially causing massive hemorrhage, shock, and even life-threatening situations. Uterine rupture may also directly result in fetal ischemia and hypoxia, leading to fetal distress, asphyxia, and other serious complications, thereby increasing the risk of adverse fetal outcomes.
For pregnant women with a scarred uterus, close monitoring of the thickness of the uterine scar is essential. Regular prenatal checkups and assessments are necessary. Ultrasound and other diagnostic methods can help timely evaluate any changes in the scarred uterus.
