Levator Hiatal Dimensions and Mode of Delivery

NCT05849584 | Withdrawn

• 1 other identifier: 423957
• Study Type: observational
• Target: N/A
• Locations: 1 country
• Sites: 2

Brief Summary

The aim of this observational study is to learn about how muscle dimensions of the pelvic floor measured during pregnancy in primigravida impact birth mecanics and mode of delivery. Tha main aims are to 1. Explore associations between mode of delivery and hiatal dimensions measured by transperineal ultrasound antenatally and 2. Explore the association between duration of 2nd stage of labour and hiatal dimensions. A pelvic floor ultrasound examination will be performed between pregnancy week 12 and 20 and levator ani muscle hiatal dimensions will be compared between women having a normal vaginal delivery and women with emergency cesarean or operative vaginal deliveries.

Conditions

Pelvic Floor; Rupture; Childbirth Problems; Pelvic Floor Dyssynergia

Outcome Measures

Primary Outcomes (3)

• Mode of delivery

  Normal vaginal, vacuum assisted vaginal, forceps assisted vaginal or emergency cesarean delivery

  Assessed at 1 day of childbirth

• Levator hiatal dimensions

  levator hiatal anteroposterior diameter and levator hiatal area at rest measured with 2D and 3D ultrasound

  Measured in pregnancy week 12

• Levator hiatal dimensions

  levator hiatal anteroposterior diameter and levator hiatal area at rest measured with 2D and 3D ultrasound

  Measured in pregnancy week 18

Secondary Outcomes (5)

• Duration of second stage of delivery

  Assessed at 1 day of childbirth

• Pernineal tears

  Assessed at 1 day of childbirth

• Postpartum haemorrage

  Assessed at 1 day of childbirth

• womans experience of transperineal ultrasound

  Assessed at pregnancy week 12 and week 18

• Interrater validity of ultrasound measurements

  Assessed 3 months after childbirth

Study Arms (1)

Pregnant women

Other: Transperineal ultrasound

Interventions

Transperineal ultrasound OTHER

A 2D scan will be performed of one experienced clinician. The average of 3 2D levator hiatal anteroposterior measurements will be stored. Then, a 3D/4D ultrasound examination of the pelvic floor will be performed using a Voluson S10, E8 or E10 (GE healthcare, Zipf, Austria) device with a RAB 4-8 MHz curved array transducer with the acquisition angle set at 85 degrees. Offline analysis of the ultrasound volumes will be performed using the 4D view (GE Healthcare, Austria) software, blinded to all clinical data. Hiatal anteroposterior diameter will be measured in both 2D and 3D. Hiatal area and hiatal transverse diameter will be measured in the 3D volume

Pregnant women

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

400 nulliparous pregnant women recruited at routine ultrasound scan i nearly pregnancy

You may qualify if:

• Age over 18 years
• Ability to consent
• Singleton pregnancy

You may not qualify if:

• Previous deliveries \> 16 weeks gestation
• Previous pelvic floor surgery
• Anomalies affecting the pelvic floor function (such as myelomeningocele)
• Epilepsy, since this might influence intervention during delivery
• Women with elective cesarean

Sponsors & Collaborators

• St. Olavs Hospital: lead

Study Sites (2)

Levanger Sykehus

Levanger, Norway

Location

st.Olavs hospital

Trondheim, Norway

Location

MeSH Terms

Conditions

Rupture

Condition Hierarchy (Ancestors)

Wounds and Injuries

Study Officials

• Ingrid Volløyhaug, PhD

  St. Olavs Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 2 Years
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 19, 2023
• First Posted: May 9, 2023
• Study Start: February 5, 2024
• Primary Completion: October 1, 2025
• Study Completion: October 1, 2025
• Last Updated: June 24, 2025

Record last verified: 2025-06

Data Sharing

• IPD Sharing: Will not share

Locations

NO (2)