Self-Obtained Ultrasound Scans for Measurement of Cervical Dilation and Effacement in Labor

Self-Obtained Transperineal and Transvaginal Ultrasound Scans for Measurement of Cervical Dilation and Effacement in Labor: Implications for Telemedicine and Home Hospital in Obstetrics

This is a pilot study to test the accuracy and comfort of self-directed ultrasound imaging of cervical dilation and effacement in pregnant women undergoing induction of labor. The study will assess correlation of cervical measurements between self-directed imaging and experienced provider digital cervical examinations.

The primary objective will assess correlation of cervical measurements with gold standard of provider digital cervical examinations and self-obtained transperineal and transvaginal images. Experienced providers performing digital cervical examinations will be blinded to ultrasound images and measurements. The maternal-fetal medicine subspecialist interpreting the ultrasound images will be blinded to patient details and will document ultrasound measurement of cervical dilation of the internal cervical os as the mean of anterior-posterior and transverse measurements and cervical length. 2-D ultrasound images and cine clips will be obtained at up to five different time points during the induction of labor.

As as secondary objective, participant discomfort and anxiety will be measured following the initial set of cervical measurements using the Visual Analog Scale and Six-Item State-Trait Anxiety Inventory.

Inclusion Criteria:

• Pregnant females age 18 years or older
• Third trimester of pregnancy with a singleton fetus (gestational age >28 weeks)
• Pre-gestational body mass index <40
• Scheduled for induction of labor
• Eligible for induction of labor based on current birth center guidelines
• Intact membranes when presenting for induction of labor

Exclusion Criteria:

• History of prior cervical loop electrosurgical excisional procedure or cold knife conization
• Cerclage placement during current pregnancy
• Positive COVID-19 test within 7 days of admission for induction of labor
• Fever > 38.0 C at time of admission for induction of labor