Unintentional Extensions of the Cesarean Hysterotomy Incision: A Review and Proposed Classification System

Area of Science:

• Obstetrics and Gynecology
• Surgical Complications

Background:

• Unintentional hysterotomy extensions are common but poorly defined complications of cesarean delivery.
• These extensions are associated with significant maternal morbidity.

Purpose of the Study:

• To synthesize evidence on the definition, incidence, risk factors, sequelae, and prevention of hysterotomy extensions.
• To highlight the need for standardized terminology and further research.

Main Methods:

• Narrative review of observational and interventional studies.
• Synthesis of data on risk factors, outcomes, and preventative strategies.

Main Results:

• Cesarean delivery during the second stage of labor is the strongest predictor of hysterotomy extensions.
• Extensions are associated with increased blood loss, transfusion rates, operative time, and intraoperative injury.
• Evidence on subsequent uterine rupture is conflicting; some studies suggest increased risk of preterm birth in future pregnancies.

Conclusions:

• Unintentional hysterotomy extension is a frequent, morbid, and underrecognized complication of cesarean birth.
• Standardized terminology, a grading system, and higher-quality prospective data are necessary.
• Certain delivery methods may reduce the incidence of hysterotomy extensions.