Fetal Scalp Stimulation Versus Fetal Blood Sampling in Labour

NCT05306756 | Terminated DMC

• 1 other identifier: DIFA019
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

Pregnant women have routine monitoring of the baby's heart rate when in labour. Women with complicated pregnancies require continuous monitoring using an electronic recorder called a CTG. The CTG produces a paper based recording which is interpreted by the midwife as showing normal, suspicious or abnormal features of the baby's heart rate. Babies quite commonly demonstrate abnormal features from time to time during the course of labour. In some cases the abnormal features are of sufficient concern to warrant delivery by emergency caesarean section. In most of these cases the baby is born in good condition and the question arises whether the caesarean section was unnecessary. In order to reduce the chance of an unnecessary caesarean section additional "second-line" tests can be offered. One such test is where a small drop of blood is taken from the baby's scalp. This test involves an internal examination with an instrument to visualise the baby's head and a small scratch to the baby's scalp. The blood is tested for acid which is an indicator of whether or not the baby is receiving enough oxygen. The test is called a fetal blood sample or FBS. An alternative test is where the doctor or midwife performs a vaginal examination with two fingers and gently rubs the baby's scalp in an attempt to cause an increase in the baby's heart rate. This is a healthy response suggesting that the baby is receiving enough oxygen. The test is called digital fetal scalp stimulation or dFSS. These two "second-line" tests have never been compared in a properly conducted head-to-head comparison. This study aims to compare dFSS and FBS in a large clinical trial completed within four of Ireland's largest maternity hospitals. This trial will generate important evidence of direct relevance to clinical care and patient outcomes.

Conditions

Intrapartum Fetal Distress

Keywords

randomised controlled trial; fetal blood sampling; fetal scalp stimulation; cardiotocography; caesarean section

Outcome Measures

Primary Outcomes (1)

• Caesarean section (CS)

  All caesarean sections will be in labour in the context of an abnormal CTG

  at birth

Secondary Outcomes (25)

• Caesarean section , primary indication fetal concerns

  at birth

• Caesarean section, primary indication poor progress

  at birth

• Caesarean section, failed attempt at assisted vaginal birth

  at birth

• Assisted vaginal birth (AVB) (all cases)

  at birth

• Assisted vaginal birth, primary indication fetal concerns

  at birth

Study Arms (2)

Fetal Blood Sampling (FBS)

ACTIVE COMPARATOR

Fetal capillary blood samples will be collected in heparinised tubes and analysed in the delivery suite using the locally available gas analyser. The result of the first technically reliable sample, or the lowest reliable sample if multiple samples are tested, will be interpreted and acted upon according to the protocol, taking account of the clinical circumstances and the stage of labour: pH ≥7.25 normal, continue and if indicated repeat in 60 minutes; pH 7.21-7.24 borderline, repeat in 30 minutes; pH ≤ 7.20 abnormal, deliver.

Diagnostic Test: Fetal Blood Sampling (FBS)

digital Fetal Scalp Stimulation (dFSS)

ACTIVE COMPARATOR

The examiner will stimulate the fetal scalp digitally with the index and middle finger over a period of 30-60 seconds.The CTG will be observed over a 5-10 minutes interval after the dFSS and if a fetal heart rate acceleration (\>15 bpm for 15 seconds) is observed the test will be considered normal. If there is an episode of normal variability (5-25 bpm) but there is no clear acceleration, the test will be considered borderline. If there is no FHR acceleration and no episode of normal variability with ongoing abnormal features, the test should be interpreted as abnormal in the same way as an abnormal FBS result. FHR acceleration normal, if indicated repeat in 60 min; Uncertain acceleration/ normal variability borderline, repeat in 30 minutes; No Acceleration/ongoing abnormal features abnormal, deliver.

Diagnostic Test: digital Fetal Scalp Stimulation (dFSS)

Interventions

Fetal Blood Sampling (FBS) DIAGNOSTIC_TEST

Vaginal examination, insert amnioscope through cervix, visualise fetal scalp, clean fetal scalp, apply ethyl chloride spray, wipe scalp with petroleum gel, small scalp scratch with sharp instrument, collect sample in heparinised capillary tube, analyse sample.

Fetal Blood Sampling (FBS)

digital Fetal Scalp Stimulation (dFSS) DIAGNOSTIC_TEST

Vaginal examination, insert one or two fingers through cervix onto fetal scalp, rub fetal scalp digitally for approximately 30-60 seconds, withdraw fingers and observe CTG for 5-10 minutes.

digital Fetal Scalp Stimulation (dFSS)

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Nulliparous women
• Singleton pregnancy
• Cephalic presentation
• Gestational age 37+0 weeks or greater
• Abnormal CTG that requires second-line testing (FBS or dFSS)

You may not qualify if:

• Contraindication to FBS
• Limited understanding of English
• At the discretion of the responsible obstetrician in cases where there is urgency

Sponsors & Collaborators

• University of Dublin, Trinity College: lead
• University College Cork: collaborator
• University of Limerick: collaborator
• Royal College of Surgeons, Ireland: collaborator
• National University of Ireland, Galway, Ireland: collaborator
• Health Research Board, Ireland: collaborator
• Health Research Board - Trials Methodology Research Network: collaborator

Study Sites (1)

Coombe Women & Infants University Hospital

Dublin, D8, Ireland

Location

Related Publications (3)

• Hughes O, Murphy DJ. Comparing second-line tests to assess fetal wellbeing in Labor: a feasibility study and pilot randomized controlled trial. J Matern Fetal Neonatal Med. 2022 Jan;35(1):91-99. doi: 10.1080/14767058.2020.1712704. Epub 2020 Jan 12.

  PMID: 31928269 BACKGROUND

• Yambasu S, Boland F, O'Donoghue K, Curran C, Shahabuddin Y, Cotter A, Gaffney G, Devane D, Molloy EJ, Murphy DJ. Digital Foetal Scalp Stimulation Versus Foetal Blood Sampling to Assess Foetal Well-Being in Labour: A Multicentre Randomised Controlled Trial. BJOG. 2025 Apr;132(5):557-564. doi: 10.1111/1471-0528.18068. Epub 2025 Jan 9.

  PMID: 39780658 DERIVED

• Murphy DJ, Shahabuddin Y, Yambasu S, O'Donoghue K, Devane D, Cotter A, Gaffney G, Burke LA, Molloy EJ, Boland F. Digital fetal scalp stimulation (dFSS) versus fetal blood sampling (FBS) to assess fetal wellbeing in labour-a multi-centre randomised controlled trial: Fetal Intrapartum Randomised Scalp Stimulation Trial (FIRSST NCT05306756). Trials. 2022 Oct 4;23(1):848. doi: 10.1186/s13063-022-06794-9.

  PMID: 36195894 DERIVED

Study Officials

• Deirdre J Murphy, MD

  Trinity College, University of Dublin

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: The primary and perinatal secondary outcomes will be recorded from the computerised delivery record without knowledge of the allocation. The principal investigator will play no role in the care of the patient or assessment of outcomes.
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Obstetrics

Model Details: Patients in labor with CTG abnormalities that warrant second-line testing of fetal wellbeing - randomized to digital fetal scalp stimulation (dFSS) versus fetal blood sampling (FBS)

Study Record Dates

• First Submitted: March 14, 2022
• First Posted: April 1, 2022
• Study Start: May 10, 2022
• Primary Completion: May 1, 2023
• Study Completion: August 31, 2023
• Last Updated: February 20, 2024

Record last verified: 2024-02

Data Sharing

• IPD Sharing: Will not share

Locations

IE (1)