Fetal MonitoringNCT04779294
The Oslo Stan vs Lactate Observational Study
An observational study of Fetal Monitoring, run by Oslo University Hospital at 1 site in Norway.
Trial summary
The main aim of the study is to compare the clinical performance of two adjunctive methods to CTG in intrapartum fetal monitoring: FBS with measurement of scalp lactate and ST analysis of the fetal ECG. Read more about this study
- Who is it for?
- Ages 18 to 60 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Fetal Monitoring
- What is being tested?
- STAN ( St wave analysis) and fetal blood sample-lactate
- How many people
- 694 participants
- Where
- 1 siteNorway
- Study dates
- 1 Sep 2018to 31 Oct 2023
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- Women only
- Healthy volunteers accepted
- Adult
Study population: Women in labour who are monitored with CTG and FBS scalp lactate. CTG monitoring is achieved by an internal scalp electrode combined with a pressure-sensitive external contraction transducer. FBS is performed at the decision of the obstetrician. Capillary blood is obtained from the fetal head and analyzed with a bed-side test (Lactate Pro). The monitoring procedures described above are identical with the current clinical routine at the department. The department utilizes S31 fetal monitors (Neoventa Medical AB©, Sweden), which are equipped with the hard and software tool for ST analysis. Once the scalp electrode is attached, ST analysis will be performed and recorded continuously. ST information is blinded in labor, i.e. clinical management will only be based on CTG and FBS if indicated.
Who may be able to join
- Singleton pregnancy
- Cephalic presentation
- Gestational age ≥36+0 weeks at delivery
- Presence of antpartum or intrapartum risk factors for fetal hypoxia according to Norwegian guidelines and therefore indication for electronic fetal monitoring with scalp electrode .
Who cannot join
- Multiple pregnancies
- Breech presentation
- Gestational age < 36+0 weeks
- Contraindications for placement of a scalp electrode (HIV or HBV or HCV pos)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The Oslo Stan vs Lactate Observational Study, an Observational Study Were we Compare the Clinical Performance of Two Adjunctive Methods to CTG in Intrapartum Fetal Monitoring
The main aim of the study is to compare the clinical performance of two adjunctive methods to CTG in intrapartum fetal monitoring: FBS with measurement of scalp lactate and ST analysis of the fetal ECG.
Read the detailed description
We use Lactate as a standard adjunctive method in our hospital but we have STAN software available ( is demasked) in our CTG monitors. We will include all women in labour with an intern scalp monitoring and analyse the CTG, the lactate samples and the STAN signals in the same patient and
- Study the relationship between the decision-to-delivery interval and neonatal morbidity in deliveries monitored by scalp lactate measurement
- Compare the diagnostic capability of both methods to identify fetuses at risk of hypoxia
- Compare the false negative alerts from both methods
- Explore the temporal and quantitative relation between fetal lactate metabolism and ST interval changes of the fetal ECG
- Investigate the occurrence of fetal extrasystoles during labor and to assess their association with short-term neonatal outcomes
- Conditions
- Fetal Monitoring
- Being tested
- STAN ( St wave analysis) and fetal blood sample-lactate
- Keywords
- CTG, Fetal blood sampling - Lactate, ST waveform analysis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
STAN ( St wave analysis) and fetal blood sample-lactateDiagnostic test
The CTG will be analysed by an expert group additional to the standard procedure that have been done in Labour already. The STAN analysis will be decrypted/ demasked anonymously by the Company producing these machines.
| Study group | Role | What they receive |
|---|---|---|
| Fetus in labour at risk of acedimia | The Group of patients studied are fetuses in labour at risk of hypoxia with internal fetal monitoring and scalp lactate bloodsamples ( standard monitoring). Receives: Diagnostic Test: STAN ( St wave analysis) and fetal blood sample-lactate | |
| Fetus in labour at risk of acedemia with STAN analysis | Same group of fetuses in labour at risk of hypoxia with internal fetal monitoring and STAN analysis(ST waveform analysis of the fetal electrocardiogram, opened after study inclusion finished) Receives: Diagnostic Test: STAN ( St wave analysis) and fetal blood sample-lactate |
What is being measured
The primary outcome is the main question the study is designed to answer.
Is fetal hypoxia (defined as arterial umbilical cord pH < 7,1 postpartum) superiorly identified by fetal scalp blood sampling (lactate) or ST analysis of fetal ECG
- Compare the diagnostic capability of both methods to identify fetuses at risk of hypoxia (i.e.umbilical artery blood pH ≤7.1)
- Compare FBS lactate with STAN in order to identify the superior method to avoid cord-blood acidosis at birth (i.e.umbilical artery blood pH >7.1)
- Compare the true negative alerts from both methods, specificity
Measured: 2019-2022
Is cord blood acidosis, measured as pH in the umbilical artery postpartum affected by the "Decision-to-delivery interval" measured in minutes from Lactate warning until delivery.
To assess the effect of increasing time interval from the objective warning of intrapartum fetal hypoxia with fetal scalp lactate ≥ 4.8mmol/l to the end of operative delivery on the percentage of moderate cord-blood acidosis at birth (i.e., umbilical artery blood pH ≤ 7.1)
Measured: 2019-2022
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Mar 2021
- Study start1 Sep 2018
- Primary completion31 Dec 2019
- Study completion31 Oct 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for Fetal MonitoringStudies of the same condition, open and under way.
- More trials run by Oslo University HospitalThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 694 participants (actual)
Sponsor and investigators
- Lead sponsor
- Oslo University Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Haukeland University Hospital
- Responsible party
- Principal investigator, Anne Flem Jacobsen, Oslo University Hospital
- Investigators
- Jacobsen F Anne Flem, MD, PhD, Study director, OUH
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04779294
- Sponsor's protocol ID
- 2017/1561
- Status last verified
- Jun 2026
- First submitted
- 12 Dec 2019
- Last updated
- 15 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Berge MB, Kessler J, Staff AC, Jacobsen AF. The diagnostic accuracy of different fetal blood sample lactate cutoffs in labor, utilizing the StatStrip Xpress(R) lactate-meter: A population-based observational study. Acta Obstet Gynecol Scand. 2025 Aug;104(8):1496-1504. doi: 10.1111/aogs.15140. Epub 2025 Apr 30.
PubMed 40304212Berge MB, Jacobsen AF, Yli BM, Staff AC, Gunnes N, Falk RS, Helgadottir LB, Kessler J. A direct comparison of the diagnostic accuracy of ST segment analysis (STAN) and fetal scalp blood sample lactate: A population-based observational study. Eur J Obstet Gynecol Reprod Biol. 2025 Apr 17;308:147-152. doi: 10.1016/j.ejogrb.2025.03.002. Epub 2025 Mar 3.
PubMed 40054097Berge MB, Kessler J, Yli BM, Staff AC, Gunnes N, Jacobsen AF. Neonatal outcomes associated with time from a high fetal blood lactate concentration to operative delivery. Acta Obstet Gynecol Scand. 2023 Aug;102(8):1106-1114. doi: 10.1111/aogs.14597. Epub 2023 Jun 7.
PubMed 37287317
Study at a glance
From the registry record, last updated by the sponsor on 15 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Oslo Stan vs Lactate Observational Study, an Observational Study Were we Compare the Clinical Performance of Two Adjunctive Methods to CTG in Intrapartum Fetal Monitoring
- ClinicalTrials.gov ID
- NCT04779294
- Acronym / sponsor ID
- 2017/1561
- Conditions
- Fetal Monitoring
- Keywords
- CTG, Fetal blood sampling - Lactate, ST waveform analysis
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 694 participants (actual)
- Lead sponsor
- Oslo University HospitalUniversity, hospital or other
- Collaborators
- Haukeland University Hospital
- Study start
- 1 Sep 2018 (actual)
- Primary completion
- 31 Dec 2019 (actual)
- Study completion
- 31 Oct 2023 (actual)
- First posted
- 3 Mar 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The main aim of the study is to compare the clinical performance of two adjunctive methods to CTG in intrapartum fetal monitoring: FBS with measurement of scalp lactate and ST analysis of the fetal ECG.
Detailed description
We use Lactate as a standard adjunctive method in our hospital but we have STAN software available ( is demasked) in our CTG monitors. We will include all women in labour with an intern scalp monitoring and analyse the CTG, the lactate samples and the STAN signals in the same patient and
- Study the relationship between the decision-to-delivery interval and neonatal morbidity in deliveries monitored by scalp lactate measurement
- Compare the diagnostic capability of both methods to identify fetuses at risk of hypoxia
- Compare the false negative alerts from both methods
- Explore the temporal and quantitative relation between fetal lactate metabolism and ST interval changes of the fetal ECG
- Investigate the occurrence of fetal extrasystoles during labor and to assess their association with short-term neonatal outcomes
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Fetus in labour at risk of acedimia | – | Diagnostic Test: STAN ( St wave analysis) and fetal blood sample-lactateThe Group of patients studied are fetuses in labour at risk of hypoxia with internal fetal monitoring and scalp lactate bloodsamples ( standard monitoring). |
| Fetus in labour at risk of acedemia with STAN analysis | – | Diagnostic Test: STAN ( St wave analysis) and fetal blood sample-lactateSame group of fetuses in labour at risk of hypoxia with internal fetal monitoring and STAN analysis(ST waveform analysis of the fetal electrocardiogram, opened after study inclusion finished) |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Women in labour who are monitored with CTG and FBS scalp lactate. CTG monitoring is achieved by an internal scalp electrode combined with a pressure-sensitive external contraction transducer. FBS is performed at the decision of the obstetrician. Capillary blood is obtained from the fetal head and analyzed with a bed-side test (Lactate Pro). The monitoring procedures described above are identical with the current clinical routine at the department. The department utilizes S31 fetal monitors (Neoventa Medical AB©, Sweden), which are equipped with the hard and software tool for ST analysis. Once the scalp electrode is attached, ST analysis will be performed and recorded continuously. ST information is blinded in labor, i.e. clinical management will only be based on CTG and FBS if indicated.
Key inclusion criteria (4 listed)
- Singleton pregnancy
- Cephalic presentation
- Gestational age ≥36+0 weeks at delivery
- Presence of antpartum or intrapartum risk factors for fetal hypoxia according to Norwegian guidelines and therefore indication for electronic fetal monitoring with scalp electrode .
Key exclusion criteria (4 listed)
- Multiple pregnancies
- Breech presentation
- Gestational age < 36+0 weeks
- Contraindications for placement of a scalp electrode (HIV or HBV or HCV pos)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| STAN ( St wave analysis) and fetal blood sample-lactateThe CTG will be analysed by an expert group additional to the standard procedure that have been done in Labour already. The STAN analysis will be decrypted/ demasked anonymously by the Company producing these machines. | Diagnostic test | Fetus in labour at risk of acedemia with STAN analysis, Fetus in labour at risk of acedimia |
Primary outcome
Is fetal hypoxia (defined as arterial umbilical cord pH < 7,1 postpartum) superiorly identified by fetal scalp blood sampling (lactate) or ST analysis of fetal ECG
Time frame: 2019-2022
1. Compare the diagnostic capability of both methods to identify fetuses at risk of hypoxia (i.e.umbilical artery blood pH ≤7.1) 2. Compare FBS lactate with STAN in order to identify the superior method to avoid cord-blood acidosis at birth (i.e.umbilical artery blood pH >7.1) 3. Compare the true negative alerts from both methods, specificity
Is cord blood acidosis, measured as pH in the umbilical artery postpartum affected by the "Decision-to-delivery interval" measured in minutes from Lactate warning until delivery.
Time frame: 2019-2022
To assess the effect of increasing time interval from the objective warning of intrapartum fetal hypoxia with fetal scalp lactate ≥ 4.8mmol/l to the end of operative delivery on the percentage of moderate cord-blood acidosis at birth (i.e., umbilical artery blood pH ≤ 7.1)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Jun 2026.
- Derived from this study: PubMed 40304212Berge MB, Kessler J, Staff AC, Jacobsen AF. The diagnostic accuracy of different fetal blood sample lactate cutoffs in labor, utilizing the StatStrip Xpress(R) lactate-meter: A population-based observational study. Acta Obstet Gynecol Scand. 2025 Aug;104(8):1496-1504. doi: 10.1111/aogs.15140. Epub 2025 Apr 30.
- Derived from this study: PubMed 40054097Berge MB, Jacobsen AF, Yli BM, Staff AC, Gunnes N, Falk RS, Helgadottir LB, Kessler J. A direct comparison of the diagnostic accuracy of ST segment analysis (STAN) and fetal scalp blood sample lactate: A population-based observational study. Eur J Obstet Gynecol Reprod Biol. 2025 Apr 17;308:147-152. doi: 10.1016/j.ejogrb.2025.03.002. Epub 2025 Mar 3.
- Derived from this study: PubMed 37287317Berge MB, Kessler J, Yli BM, Staff AC, Gunnes N, Jacobsen AF. Neonatal outcomes associated with time from a high fetal blood lactate concentration to operative delivery. Acta Obstet Gynecol Scand. 2023 Aug;102(8):1106-1114. doi: 10.1111/aogs.14597. Epub 2023 Jun 7.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jacobsen F Anne Flem, MD, PhD study director
OUH
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Fetal Monitoring, run by Oslo University Hospital at 1 site in Norway.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 15 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Norway. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Is fetal hypoxia (defined as arterial umbilical cord pH < 7,1 postpartum) superiorly identified by fetal scalp blood sampling (lactate) or ST analysis of fetal ECG (time frame: 2019-2022). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04779294, which also lists 3 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Jun 2026.