Standardized Approach for Imaging and Measuring Cesarean Section Scars Using Ultrasonography

Abstract

With increasing rates of cesarean section (CS), there are concerns over the associated complications, including the possible increase in adverse outcomes in later pregnancies. As CS rates continue to rise, more women are becoming pregnant with a CS scar on the uterus. Incomplete healing of a scar is a recognized complication of CS and may play a role in the occurrence of complications in a subsequent pregnancy. Such potential complications include the risk of scar pregnancy, a morbidly adherent placenta, scar dehiscence, or uterine rupture. The factors leading to poor scar healing are unclear. Ultrasound has been used to visualize the uterus and describe the morphology of CS scars when present. The aim of this report was to review and evaluate the role of sonographic scar appearance in the occurrence of complications in subsequent pregnancies. A search of the PubMed database was performed to identify articles assessing uterine scars by ultrasound as well as variation in nomenclature, definitions, and methods of scar evaluation. Several recent studies have described scars as poorly, incompletely, or inadequately healed and/or deficient based on ultrasound findings. However, there are few data to justify the association of scar morphology with the functional integrity of the lower uterine segment. Investigators have used different terminology and methods of classifying CS scars and obtained different results. Currently, there is no consensus regarding the prevalence, clinical significance, or most appropriate method to describe the morphology of the scars. A scar described as “deficient” based on an ultrasound examination may lead to inappropriate clinical decision making. In this report, the authors propose a method based on objective measurement using transvaginal ultrasonography to describe CS scars. Examination of the literature shows that standardizing nomenclature is needed to allow useful comparisons among future studies that investigate the possible relationship between scars and complications in subsequent pregnancies.