MedPath

Intrapartum Ultrasound for Assessment of Fetal Progression

Not Applicable
Not yet recruiting
Conditions
Labor, Obstetric
Interventions
Other: Transperineal imaging
Registration Number
NCT05718180
Lead Sponsor
University of Padova
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, HSD, HPD, PAA 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.

Detailed Description

Not available

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
Female
Target Recruitment
177
Inclusion Criteria
  • pregnant women with singleton pregnancies
  • at term gestation (37 weeks)
  • fetus in cephalic presentation
  • absence of factors hindering vaginal delivery
Exclusion Criteria
  • complicated pregnancies
  • vaginal birth after Cesarean
  • twin pregnancies
  • early pregnancy
  • women condition that exclude vaginal birth

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
FlexibleTransperineal imagingMeasures are performed first in a kneeling squat position and then in the supine position
SupineTransperineal imagingMeasures are performed first in the supine position and then in a flexible sacrum position
Primary Outcome Measures
NameTimeMethod
Ultrasound AoP RSDuring the resting step

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

Ultrasound MLA RSDuring the resting step

To measure MLA (MidlineAngle) expressed in degrees in the supine position and kneeling squat position in the same woman during the resting step up to 3 hours

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

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

Ultrasound HPD PDuring the push

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

Ultrasound AoP PDuring the push

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

Ultrasound HSD RSDuring the resting step

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

Ultrasound HSD PDuring the push

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

Ultrasound MLA PDuring the push

To measure MLA (MidlineAngle) expressed in degrees in the supine position and kneeling squat position in the same woman during the push up to 3 hours

Ultrasound PAA RSDuring the resting step

To measure the PAA (pubic arch angle) expressed in degrees in the supine position and kneeling squat position in the same woman during the resting step up to 3 hours

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

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

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

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

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

To measure the PAA (pubic arch angle) expressed in degrees in the supine position and kneeling squat position in the same woman during the expulsion phase up to 3 hours

Ultrasound PAA PDuring the push

To measure the PAA (pubic arch angle) expressed in degrees in the supine position and kneeling squat position in the same woman during the push up to 3 hours

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

To measure MLA (MidlineAngle) expressed in degrees in the supine position and kneeling squat position in the same woman during the expulsion up to 3 hours

Ultrasound HPD RSDuring the resting step

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

Secondary Outcome Measures
NameTimeMethod
fetal positionat the beginning of delivery

fetal position

pHWithin 1 hour after delivery

pH

duration of labour stagesduring labour stages

duration of labour stages up to 18 hours

fetal weightat delivery

fetal weight

Apgar Index at 1 min after deliveryOne minute after delivery

Apgar Index

reasons for possible caesarean sectionimmediately after caesarean section

reasons for possible caesarean section

mode of deliveryduring delivery

mode of delivery

Apgar Index 5 minutes after deliveryFive minutes after delivery

Apgar Index

BEWithin 1 hour after delivery

Bases excess

Trial Locations

Locations (3)

Azienda Ospedaliero Universitaria Sant'Orsola Malpighi

🇮🇹

Bologna, Italy

Azienda Ospedale Università Padova

🇮🇹

Padova, Italy

Ospedale Cristo Re

🇮🇹

Roma, Italy

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