Evaluation of Image Quality in Obstetrical Ultrasonography: Comparison Between Subjective Assessment and Contrast-to-noise Ratio

The goal of this observational study is to determine whether the subjective assessment of the quality of obstetrical ultrasonography pictures can be similar to that of an objective tool. The main question it aims to answer is: Is the subjective assessment of the quality of obstetrical ultrasonography pictures by a young practitioner and an experienced one can be similar to that of an objective tool, such as the contrast-to-noise ratio (CNR)? The contrast-to-noise ratio is commonly used in radiology to evaluate image quality by assessing the ability to distinguish differences between two elements. The investigators selected a retrospective cohort of 198 patients, including three pictures per fetus screened between 18 and 18 weeks and 6 days. For each picture, the investigators assessed the quality of two different elements and the entire image, and then calculated the CNR using software. The investigators will compare the three assessment between them