Labor PainPhase 3VVAMBNCT04011150
Development of Variable Volume Automated Mandatory Boluses for Patient-controlled Epidural Analgesia During Labour
A Phase 3 study testing Epidural infusion pump, Ropivacaine and Fentanyl in people with Labor Pain and Breakthrough Pain, run by KK Women's and Children's Hospital at 1 site in Singapore.
Trial summary
A novel epidural delivery regimen was developed: Variable volume automated mandatory bolus (AMB) (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor… Read more about this study
- Who is it for?
- Ages 21 to 50 years, women only
- Conditions the study is for
- Labor Pain, Breakthrough Pain
- What is being tested?
- Epidural infusion pump, Ropivacaine and Fentanyl
- Type of treatment
- Injection or infusion, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 197 participants
- Where
- 1 siteSingapore
- Study dates
- 11 Aug 2020to 31 Aug 2027
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
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 21 to 50 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Healthy (American Society of Anesthesiologists (ASA) physical status 1 and 2) primiparous parturient at term (≥36 weeks gestation);
- Singleton fetus;
- In early labor stage (cervical dilation ≤5cm);
- Request labor epidural analgesia and able to administer combined spinal epidural analgesia (CSEA) according to protocol.
Who cannot join
- Non-cephalic fetal presentation;
- Obstetric (e.g. pre-eclampsia, premature rupture of amniotic membranes for more than 48 hours, gestational diabetes on insulin, pregnancy-induced hypertension on medication) and uncontrolled medical (e.g. cardiac disease) complications;
- Have contraindications to neuraxial blockade or have received parenteral opioids within last 2 hours;
- Dural puncture/ suspected dural puncture at initiation of CSEA.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Development of Variable Volume Automated Mandatory Boluses (VVAMB) for Patient-controlled Epidural Analgesia During Labour and Delivery
A novel epidural delivery regimen was developed: Variable volume automated mandatory bolus (AMB) (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries.
Read the detailed description
Epidural analgesia is the gold standard of pain relief for labour pain. Despite this, up to 50% of parturients continue to experience pain leading to suffering and increased caregiver workload. There is also higher risk of motor blockade found in those receiving epidural analgesia, and these factors is associated with dysfunctional labour requiring obstetric intervention (instrumental delivery). Automated mandatory bolus (AMB) of variable-frequency (VAMB) has been shown to provide better pain relief as compared with conventional patient-controlled epidural analgesia (PCEA) with basal infusion, however its long lockout time per hour is associated with unsuccessful patient bolus requests, with similar motor block to conventional regimens.
The investigators therefore proposes to develop a novel epidural delivery regimen: Variable volume AMB (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries. This algorithm development including pilot and clinical trial will compare VVAMB with VAMB regimens, in reducing the incidence of motor block in term women requesting for labour epidural analgesia.
- Conditions
- Labor Pain, Breakthrough Pain
- Being tested
- Epidural infusion pump, Ropivacaine, Fentanyl
- Keywords
- Labor Pain, Breakthrough Pain, Infusion pump
- Medical subject headings
- Labor Pain, Breakthrough Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Epidural infusion pumpDevice
Also called Epidural delivery system
Epidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution.
RopivacaineDrug
Also called Amide local anaesthetic
Epidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution.
FentanylDrug
Also called Opioid
Epidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution.
| Study group | Role | What they receive |
|---|---|---|
| Variable volume Automated Mandatory Bolus (VVAMB) | Experimental | The anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VVAMB programme. The programme uses higher doses with lower frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour. Receives: Device: Epidural infusion pump; Drug: Ropivacaine; Drug: Fentanyl |
| Automated mandatory bolus (AMB) of variable-frequency (VAMB) | Active comparator | The anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VAMB programme. The programme uses lower doses with more frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour. Receives: Device: Epidural infusion pump; Drug: Ropivacaine; Drug: Fentanyl |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of motor block in each group
The number of event of motor block throughout the labour. Previous studies have shown that epidural analgesia using high concentrations of local anaesthetics could lead to decreased motor functions, and are subsequently associated with an increased incidence of instrumented delivery and longer second stage of labour. In this study, the intensity of motor block is assessed by the patient's ability to move their lower extremities via a modified Bromage scale. In the modified version, a scoring of 0 implies no motor block (Free movement of both legs and feet), scoring of 1 implies partial block (Just able to flex knees with free movement of feet), 2 implies almost complete block (Unable to flex knees but with free movement of feet) and 3 implies a full block (Unable to move legs/ feet).
Measured: During labour (1 day)
Secondary outcomes (4)
Number of subjects with Instrumental delivery
The number of subjects in each group having instrumental delivery (forceps, vacuum delivery)
Measured: During labour (1 day)
Number of subjects with Breakthrough pain
The number of subjects in each group having unscheduled epidural supplementation by anaesthetist due to labor pain
Measured: During labour (1 day)
APGAR score
The Appearance, Pulse, Grimace, Activity, and Respiration (APGAR) score is a test given to newborns soon after birth. In the test, five are being evaluated: Appearance (skin color), Pulse (heart rate), Grimace response (reflexes), Activity (muscle tone) and Respiration (breathing rate and effort). Each is scored on a scale of 0 to 2, with 2 being the best score; a total score of ten represents the best possible condition.
Measured: After delivery (1 day)
The incidence of postnatal depression in both groups
Incidence of postnatal depression will be assessed via Edinburgh Postnatal Depression Scale (EPDS) score at week 8 after delivery. EPDS is a 10-item self reporting scale to evaluate the postnatal depression. Participants are asked to respond according to how they have felt in the past seven days. Each item is measured on a 4-point scale (0-3), with a total score in the range of 0 to 30. A higher total score indicates a greater degree of depressive symptoms. A score of 10 and above indicates clinically significant depressive symptoms.
Measured: 6-10 weeks after delivery (1 day)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jul 2019
- Study start11 Aug 2020
- Primary completion28 Jul 2022
- Study completion31 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Labor PainStudies of the same condition, open and under way.
- More trials run by KK Women's and Children's 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
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 197 participants (actual)
Sponsor and investigators
- Lead sponsor
- KK Women's and Children's Hospital
- Sponsor type
- Other government
- Responsible party
- Principal investigator, Sng Ban Leong, KK Women's and Children's Hospital
- Investigators
- Wan Ling Leong, FANZCA, Principal investigator, KK Women's and Children's Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04011150
- Sponsor's protocol ID
- AM/CT001/2018
- Acronym
- VVAMB
- Status last verified
- Aug 2026
- First submitted
- 4 Jul 2019
- Last updated
- 14 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 14 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Development of Variable Volume Automated Mandatory Boluses (VVAMB) for Patient-controlled Epidural Analgesia During Labour and Delivery
- ClinicalTrials.gov ID
- NCT04011150
- Acronym / sponsor ID
- VVAMB / AM/CT001/2018
- Conditions
- Labor Pain, Breakthrough Pain
- Keywords
- Labor Pain, Breakthrough Pain, Infusion pump
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 197 participants (actual)
- Lead sponsor
- KK Women's and Children's HospitalOther government
- Study start
- 11 Aug 2020 (actual)
- Primary completion
- 28 Jul 2022 (actual)
- Study completion
- 31 Aug 2027 (estimated)
- First posted
- 8 Jul 2019 (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.
A novel epidural delivery regimen was developed: Variable volume automated mandatory bolus (AMB) (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries.
Detailed description
Epidural analgesia is the gold standard of pain relief for labour pain. Despite this, up to 50% of parturients continue to experience pain leading to suffering and increased caregiver workload. There is also higher risk of motor blockade found in those receiving epidural analgesia, and these factors is associated with dysfunctional labour requiring obstetric intervention (instrumental delivery). Automated mandatory bolus (AMB) of variable-frequency (VAMB) has been shown to provide better pain relief as compared with conventional patient-controlled epidural analgesia (PCEA) with basal infusion, however its long lockout time per hour is associated with unsuccessful patient bolus requests, with similar motor block to conventional regimens.
The investigators therefore proposes to develop a novel epidural delivery regimen: Variable volume AMB (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries. This algorithm development including pilot and clinical trial will compare VVAMB with VAMB regimens, in reducing the incidence of motor block in term women requesting for labour epidural analgesia.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Variable volume Automated Mandatory Bolus (VVAMB) | Experimental | Device: Epidural infusion pump, Drug: Ropivacaine, Drug: FentanylThe anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VVAMB programme. The programme uses higher doses with lower frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour. |
| Automated mandatory bolus (AMB) of variable-frequency (VAMB) | Active comparator | Device: Epidural infusion pump, Drug: Ropivacaine, Drug: FentanylThe anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VAMB programme. The programme uses lower doses with more frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour. |
Who may qualify
- Ages
- 21 to 50 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Healthy (American Society of Anesthesiologists (ASA) physical status 1 and 2) primiparous parturient at term (≥36 weeks gestation);
- Singleton fetus;
- In early labor stage (cervical dilation ≤5cm);
- Request labor epidural analgesia and able to administer combined spinal epidural analgesia (CSEA) according to protocol.
Key exclusion criteria (4 listed)
- Non-cephalic fetal presentation;
- Obstetric (e.g. pre-eclampsia, premature rupture of amniotic membranes for more than 48 hours, gestational diabetes on insulin, pregnancy-induced hypertension on medication) and uncontrolled medical (e.g. cardiac disease) complications;
- Have contraindications to neuraxial blockade or have received parenteral opioids within last 2 hours;
- Dural puncture/ suspected dural puncture at initiation of CSEA.
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 |
|---|---|---|
| Epidural infusion pumpAlso: Epidural delivery systemEpidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution. | Device | Automated mandatory bolus (AMB) of variable-frequency (VAMB), Variable volume Automated Mandatory Bolus (VVAMB) |
| RopivacaineAlso: Amide local anaestheticEpidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution. | Drug | Automated mandatory bolus (AMB) of variable-frequency (VAMB), Variable volume Automated Mandatory Bolus (VVAMB) |
| FentanylAlso: OpioidEpidural delivery system for maintenance of labour epidural analgesia using 0.1% ropivacaine (amide local anaesthetic) with 2mcg/ml fentanyl (opioid) as maintenance solution. | Drug | Automated mandatory bolus (AMB) of variable-frequency (VAMB), Variable volume Automated Mandatory Bolus (VVAMB) |
Primary outcome
Incidence of motor block in each group
Time frame: During labour (1 day)
The number of event of motor block throughout the labour. Previous studies have shown that epidural analgesia using high concentrations of local anaesthetics could lead to decreased motor functions, and are subsequently associated with an increased incidence of instrumented delivery and longer second stage of labour. In this study, the intensity of motor block is assessed by the patient's ability to move their lower extremities via a modified Bromage scale. In the modified version, a scoring of 0 implies no motor block (Free movement of both legs and feet), scoring of 1 implies partial block (Just able to flex knees with free movement of feet), 2 implies almost complete block (Unable to flex knees but with free movement of feet) and 3 implies a full block (Unable to move legs/ feet).
4 secondary outcomes
Number of subjects with Instrumental delivery
Time frame: During labour (1 day)
Number of subjects with Breakthrough pain
Time frame: During labour (1 day)
APGAR score
Time frame: After delivery (1 day)
The incidence of postnatal depression in both groups
Time frame: 6-10 weeks after delivery (1 day)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Aug 2026.
- 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.
Wan Ling Leong, FANZCA principal investigator
KK Women's and Children's Hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Epidural infusion pump, Ropivacaine and Fentanyl in people with Labor Pain and Breakthrough Pain, run by KK Women's and Children's Hospital at 1 site in Singapore.
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: under way, not looking for participants, as of the sponsor's last update on 14 Aug 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 Singapore. 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.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
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?
Incidence of motor block in each group (time frame: During labour (1 day)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 14 Aug 2026.