Related Experiment Video
Updated: Jun 24, 2026

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System
Published on: September 20, 2018
How reliable is the determination of cervical dilation? Comparison of vaginal examination with spatial
Jacky Nizard1, Shoshana Haberman, Yoav Paltieli
1Department of Obstetrics and Gynecology, CHI Poissy Saint Germain, Université de Versailles, Saint-Quentin-en-Yvelines, France.
Objective:
The purpose of this study was to evaluate the accuracy of clinical measurement of cervical dilation with a position-tracking system during vaginal examination.
Study Design:
This prospective study that was conducted in Poissy, France, Brooklyn, NY, and Haifa, Israel, included 333 measurements that were performed in 188 women with term singleton vertex uncomplicated pregnancies during the active stage of labor. Ninety measurements with clinical diagnosis of full dilation were excluded from analysis. Measurements were performed with a sensor attached to the midwife's index fingertip and a position-tracking system that was based on a low magnetic field. Evaluations were done when cervical examinations were clinically indicated.
Results:
Results were similar in all centers. Mean error was 10.2 +/- 8.4 mm and ranged from 7.5 +/- 7.3 mm, when cervical dilation was > 8 cm, to 12.5 +/- 8.7 mm when cervical dilation was between 6.1 and 8 cm.
Conclusion:
This first evaluation of cervical assessment accuracy during vaginal examination with a position-tracking system shows limited precision.
Related Concept Videos
Adjusting a Traverse
Distance Corrections
Assessing Body Temperature - Rectal
Follow these steps for rectal temperature assessment:
Step 1: Perform hand hygiene and don clean gloves to prevent cross-infection.
Step 2: Position the patient in a side-lying position to better visualize the rectal...

