Cervimetry: a review of methods for measuring cervical dilatation during labor.

Several different methods of measuring cervical dilatation have been described. In this article, we review those methods and examine findings from studies using them. Although many instruments have been developed to measure cervical dilatation during labor and their use as a research tool has been established, no device has yet been successfully used for clinical obstetrics. The ideal device has not yet been developed; however, because repeated digital cervical examinations are time consuming for the clinician, are poorly reproducible, and are uncomfortable for the patient, continued efforts to develop a cervimeter suitable for clinical use is a worthwhile endeavor.