Jessica Schmitz1, Holger Stepan2, Susanne Schrey-Petersen2, Janine Hoffmann2.
Abstract
INTRODUCTION: Lower uterine segment (LUS) thickness measurement is frequently used to select patients for trial of labor after a previous cesarean section (TOLAC). To date no significant benefit of LUS measurement has ever been proven, and no standard protocol or clear cut-off value exists. The aim of this study was to evaluate the benefit of LUS measurement in a daily routine setting.
MATERIAL AND METHODS: In this retrospective study, we evaluated 631 pregnancies after previous cesarean section (CS). Ultrasound measurements of myometrial (mLUS) and/or full LUS (fLUS) thickness were performed in 399 (63%) patients. The incidence, time, and mode of detection of uterine defects were studied. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated for different cut-off values of LUS thickness.
RESULTS: Uterine defects were diagnosed in 28 (4.4%) patients. Detection rate of ultrasound was low (13.6%), with better sensitivity, specificity, PPV, and NPV at lower (2 mm (fLUS) / 1 mm (mLUS): 75/96/48.3/98.7%) than at higher cut-off values (3 mm (fLUS) / 2 mm (mLUS): 15.8/93.2/10.4/68.7%). DISCUSSION: The benefit of LUS thickness measurement appears overestimated. As a large number of methodological factors trigger inaccuracy, a consistent protocol including both a transabdominal and a transvaginal scan performed by a trained examiner might improve accuracy. Exclusion of uterine defects might be more useful for prenatal selection after CS. © Georg Thieme Verlag KG Stuttgart · New York.
INTRODUCTION: Lower uterine segment (LUS) thickness measurement is frequently used to select patients for trial of labor after a previous cesarean section (TOLAC). To date no significant benefit of LUS measurement has ever been proven, and no standard protocol or clear cut-off value exists. The aim of this study was to evaluate the benefit of LUS measurement in a daily routine setting.
MATERIAL AND METHODS: In this retrospective study, we evaluated 631 pregnancies after previous cesarean section (CS). Ultrasound measurements of myometrial (mLUS) and/or full LUS (fLUS) thickness were performed in 399 (63%) patients. The incidence, time, and mode of detection of uterine defects were studied. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated for different cut-off values of LUS thickness.
RESULTS: Uterine defects were diagnosed in 28 (4.4%) patients. Detection rate of ultrasound was low (13.6%), with better sensitivity, specificity, PPV, and NPV at lower (2 mm (fLUS) / 1 mm (mLUS): 75/96/48.3/98.7%) than at higher cut-off values (3 mm (fLUS) / 2 mm (mLUS): 15.8/93.2/10.4/68.7%). DISCUSSION: The benefit of LUS thickness measurement appears overestimated. As a large number of methodological factors trigger inaccuracy, a consistent protocol including both a transabdominal and a transvaginal scan performed by a trained examiner might improve accuracy. Exclusion of uterine defects might be more useful for prenatal selection after CS. © Georg Thieme Verlag KG Stuttgart · New York.
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Mesh:
Year: 2019
PMID: 31163458 DOI: 10.1055/a-0828-8774
Source DB: PubMed Journal: Z Geburtshilfe Neonatol ISSN: 0948-2393 Impact factor: 0.685