Transperineal ultrasonography for labor management: accuracy and reliability

Area of Science:

• Obstetrics and Gynecology
• Medical Imaging
• Fetal Monitoring

Background:

• Accurate assessment of labor progression is crucial for maternal and fetal outcomes.
• Clinical digital examination is the traditional method for evaluating cervical dilatation, fetal head station, and position.
• Ultrasound offers a non-invasive alternative for assessing these parameters.

Purpose of the Study:

• To compare the accuracy of ultrasound measurements against clinical digital examinations for cervical dilatation, fetal head station, and fetal head position.
• To determine the agreement between sonographic and digital assessment methods.

Main Methods:

• A prospective, observational study was conducted in a tertiary care labor ward.
• Simultaneous digital examinations and ultrasonographic measurements were performed on 43 women in labor (79 total examinations).
• Measurements included cervical dilatation, angle of progression, head-perineum distance, and head position, with operators blinded to each other's findings.

Main Results:

• Significant correlation was found between ultrasound and digital assessment of cervical dilatation (ICC=0.82).
• Moderate correlation was observed for fetal head station using angle of progression and head-perineum distance (r=0.55, r=-0.42).
• Low agreement was noted between ultrasound and digital methods for assessing fetal head position.

Conclusions:

• Ultrasound provides reliable assessment of cervical dilatation during labor, comparable to clinical digital examination.
• Ultrasound demonstrates moderate agreement for evaluating fetal head station.
• The assessment of fetal head position using ultrasound shows limited agreement with digital examination.