Intrapartum Ultrasound for Assessment of Fetal Progression

NCT05718180 | Not Yet Recruiting

• 1 other identifier: MaPP
• Study Type: interventional
• Target: 105
• Locations: 1 country
• Sites: 3

Brief Summary

The use of ultrasound has been suggested to support the management of labour. According to several studies, ultrasound examination is more accurate and reproducible than clinical examination in diagnosing fetal head position, fetal station, and the prediction of labour arrest. Furthermore, there is growing evidence that ultrasound in labour may predict the outcome of instrumental vaginal delivery: a support to assess when an operative delivery is necessary. Ultrasound in labour can be performed using a transabdominal approach, mainly to determine head and spine position, or a transperineal approach, to assess head station and the situation at low stations. Several sonographic parameters have been proposed to evaluate the head station. Furthermore, all ultrasound parameters studied so far, have always been measured with the woman in a supine position. While the biomechanics of childbirth with its mechanisms (known as nutation, counter-nutation of the pelvis, and the coccyx retropulsion) together with maternal movement, promote fetal rotation and the adaptation of its diameters with those of the maternal pelvis, allowing to gain more room for the fetal descent. Moreover, in most of the studies on intrapartum ultrasound, the mobility of the pelvis has not been mentioned. The contracted pelvis is the absence of mobility that leads to fetal-pelvic disproportion, arrest of labour, and operative delivery. Maternal pelvis biomechanics studies by high technological techniques have shown that maternal shifting positions during pregnancy and childbirth can create more room in the pelvis for safe delivery. The external and internal pelvic diameters are closely related. For this reason, the evaluation of the mobility of the pelvis appears to be a necessary element to understand the ability of that pelvis to widen its diameters for fetal descent. The aim of the study is to measure the variation of AoP, HPD in the supine position and in kneeling-squat position in the same woman and the cut-offs of the new ultrasound parameters and predictive capacity for vaginal birth.

Conditions

Labor, Obstetric

Outcome Measures

Primary Outcomes (6)

• Ultrasound AoP EP

  To measure AoP (Angle of progression), expressed in degrees in the supine position and kneeling squat position in the same woman during the expulsion phase (EP) up to 3 hours

  Beginning of the expulsive phase (active second stage): with complete dilation and the perception of an urge to push.

• Ultrasound AoP RS

  To measure AoP (Angle of progression), expressed in degrees in the supine position and kneeling squat position in the same woman during the resting step (RS) up to 3 hours

  During the resting step

• Ultrasound AoP P

  To measure AoP (Angle of progression), expressed in degrees in the supine position and kneeling squat position in the same woman during the push (P) up to 3 hours

  During the push

• Ultrasound HPD EP

  To measure the HPD (head perineum distance) expressed in millimeters, in the supine position and kneeling squat position in the same woman during the expulsion phase up to 3 hours

  Beginning of the expulsive phase (active second stage): with complete dilation and the perception of an urge to push.

• Ultrasound HPD RS

  To measure the HPD (head perineum distance) expressed in millimeters, in the supine position and kneeling squat position in the same woman during the resting step up to 3 hours

  During the resting step

• Ultrasound HPD P

  To measure the HPD (head perineum distance) expressed in millimeters, in the supine position and kneeling squat position in the same woman during the push up to 3 hours

  During the push

Secondary Outcomes (9)

• mode of delivery

  during delivery

• duration of labour stages

  during labour stages

• Midwifery interventions during labour

  during labour (hours)

• Variation in the anteroposterior diameter of the levator hiatus

  during labour (hours)

• reasons for possible caesarean section

  immediately after caesarean section

Study Arms (1)

Pregnant women undergoing positional ultrasound assessment

EXPERIMENTAL

Before the onset of labour, the woman will be randomized to the order of the position during the intrapartum transperineal ultrasound (firstly supine position and secondly kneeling-squat, or vice-versa).

Other: Transperineal imaging

Interventions

Transperineal imaging OTHER

To measure the difference between ultrasound parameters based on maternal position: to measure the variation of Angle of progression (AoP), ), HPD(head perineum distance) expressed in millimeters, in the supine position and kneeling squat position in the same woman during the expulsion phase, in the resting step and during the push.

Pregnant women undergoing positional ultrasound assessment

Eligibility Criteria

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

You may qualify if:

• pregnant women with singleton pregnancies
• at term gestation (37 weeks)
• fetus in cephalic presentation
• absence of factors hindering vaginal delivery

You may not qualify if:

• complicated pregnancies
• vaginal birth after Cesarean
• twin pregnancies
• early pregnancy
• women condition that exclude vaginal birth

Sponsors & Collaborators

• University of Padova: lead
• Azienda Ospedaliera di Padova: collaborator

Study Sites (3)

Azienda Ospedaliero Universitaria Sant'Orsola Malpighi

Bologna, Italy

Location

Azienda Ospedale Università Padova

Padova, Italy

Location

Ospedale Cristo Re

Roma, Italy

Location

Central Study Contacts

Alessia Selmin

CONTACT

+390498214434; alessia.selmin@unipd.it

Honoria Ocagli, PhD

CONTACT

honoria.ocagli@ubep.unipd.it

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: SCREENING
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Prospective, multicenter, single-group interventional study with randomized intra-subject comparison of assessment positions.

Study Record Dates

• First Submitted: May 6, 2022
• First Posted: February 8, 2023
• Study Start: July 1, 2026
• Primary Completion (Estimated): July 31, 2029
• Study Completion (Estimated): July 31, 2029
• Last Updated: June 18, 2026

Record last verified: 2026-06

Locations

IT (3)