A vaginal birth risk, uterine rupture refers to incomplete or complete tearing of the uterus. It typically takes place during active labor, though it may develop during the late stages of pregnancy. The most common trigger for uterine rupture is the force of contractions during labor. Uterine rupture is a catastrophic event that can be life-threatening for both a mother and her child.
Types of Uterine Rupture
Incomplete Uterine Rupture
In an incomplete uterine rupture, the mother’s peritoneum remains intact. The peritoneum is the membrane that lines the abdominal cavity to support abdominal organs. It also acts as a channel for blood vessels and nerves. An incomplete uterine rupture is significantly less dangerous with fewer complications to the delivery process.
Complete Uterine Rupture
During a complete uterine rupture, the peritoneum tears and the contents of the mother’s uterus can spill into her peritoneal cavity. The peritoneal cavity is the fluid-filled gap that separates the abdomen walls and its organs. It is suggested that delivery via cesarean section (C-section) should occur within approximately 10 to 35 minutes after a complete uterine rupture occurs. The fetal morbidity rate increases dramatically after this period.
Uterine dehiscence is a similar condition to uterine rupture. It occurs when a previous uterine scar separates. It involves less bleeding, fewer layers, and less risk. The fetus, umbilical cord, and placenta remain in the uterus. Due to the less intense nature of uterine dehiscence, it typically does not require medical treatment to heal.
Risk Factors and Causes
The most common cause of a uterine rupture is a uterine scar that remains from a prior C-section. In one study, 52% of the participants had cesarean scars. For this reason, women who qualify for vaginal birth after C-section (VBAC) require extensive monitoring to prevent uterine rupture and other complications.
Other uterine rupture risk factors include:
- Dysfunctional labor
- A uterine wall thinner than 2 millimeters
- Congenital uterine anomalies that cause thin uterine walls
- Uterine surgery involving full-thickness incisions, such as a myomectomy
- Labor augmentation by prostaglandins or oxytocin
- High parity, or the number of times a women has given birth
Signs of Uterine Rupture
Unfortunately, a uterine rupture cannot be fully predicted or diagnosed before it occurs. In some cases, women experience mild symptoms that can prolong the diagnosis of a uterine rupture and increase the danger associated with it. Additionally, many of the warning signs of uterine rupture can be difficult to distinguish from other obstetric issues.
Symptoms of a uterine rupture may include:
- Excessive vaginal bleeding
- Unusual sharp pain in between contractions
- Decreased baseline uterine pressure and muscle tone
- Decrease in the frequency or intensity of contractions
- Fetal distress, including abnormalities in the fetal heart rate
- Recession of the fetus’ head back into the birth canal
- Bulging beneath the pubic bone indicating protrusion from the uterus
Treatment of Uterine Rupture
Once a uterine rupture is diagnosed, it is imperative to immediately stabilize the mother and deliver the fetus. Typically, an emergency surgical procedure, called a laparotomy, is used to explore the mother’s abdominal wall and a C-section is performed. In many cases, a maternal blood transfusion is necessary due to major blood loss. Depending on several factors, the uterus is either repaired or removed.
The treatment depends on several factors, involving:
- Type and extent of uterine rupture
- General condition of the mother
- Degree of hemorrhage
- Maternal desire to bear more children