ClinicalTrials.gg
Sign In
Not yet recruitingNCT07321379ProLabourUpdated Jan 12, 2026

Efficacy of Bicarbonate on the Risk of Assisted Delivery in Nulliparous Women With Prolonged Labour

An interventional study of Sodium bicarbonate and Placebo in Prolonged Labor and Labor Dystocia, sponsored by Copenhagen University Hospital, Hvidovre. Not yet recruiting at 3 sites in Denmark. Open to female participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-01-12.

Sponsored by Copenhagen University Hospital, Hvidovre · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
1,520
Allocation
Randomized
Ages
18 Years to 50 Years
Sex
Female
01

Study summary

The goal of this clinical trial is to learn if oral bicarbonate can treat prolonged labour in nulliparous women with prolonged labour.

The main question it aims to answer is: Do oral bicarbonate and restrictive oxytocin use reduce assisted delivery rate (emergency cesarean and vacuum/forceps delivery) in nulliparous women with prolonged labour.

Researchers will compare bicarbonate and placebo (a look-alike substance that contains no drug) to see if bicarbonate works to treat prolonged labour.

Participants will:

  • drink bicarbonate or placebo
  • have cervical dilatation reassessed after 2 hours. If still slow progression, they will follow standard protocol for oxytocin augmentation
  • will receive a questionnaire 1 month post partum to assess birth experience

1/3 of participants will have amniotic fluid lactate measured at inclusion and after 2 hours

02

Conditions studied

  • Prolonged Labor
  • Labor Dystocia

Browse trials for

Keywords

  • Labor
  • Bicarbonate
  • Caesarean section
  • Assisted birth
  • Oxytocin
  • Labor augmentation
  • Intrapartum
03

In context

Dystocia

55 studies on the registry are indexed under Dystocia; 12 are open to participants now.

This study's planned enrollment of 1,520 is above the median of 200 across 42 interventional studies indexed under Dystocia.

Browse Dystocia studies →

Lead sponsor

Copenhagen University Hospital, Hvidovre is the lead sponsor of 79 studies on the registry; 19 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 50 Years
Sexes eligible
Female
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Age ≥18 years.
  • Danish or English speaking.
  • Cephalic presentation.
  • Gestational age ≥34+0 - \<42+0 (days +weeks) at onset of labour.
  • Normal foetal heart rate pattern in the 20 minutes prior to inclusion.
  • Spontaneous onset of labour or non-medical induced labour (balloon catheter and/or artificial rupture of membranes).
  • Active first stage of labour confirmed, according to Danish national guidelines: Cervical dilatation at ≥4 - \<10 cm with regular painful contractions.
  • Prolonged labour diagnosed, according to Danish national guidelines: Cervical dilatation progresses at less than 2 cm over a 4-hour period.

Exclusion criteria

Exclusion Criteria:

  • Clinical suspicion of infection (2 confirmed temperatures ≥38.5°C with epidural, ≥38 °C without epidural, or broad-spectrum antibiotics initiated)
  • Significant medical comorbidity in the form of renal or heart condition, assessed case-by-case basis.
  • Serious obstetric complication
  • Known allergy or intolerance to sodium bicarbonate.
  • Ingestion of sodium bicarbonate in active labour prior to inclusion.
  • Current treatment with following medicines: Gabpabpentin, Tetracycline, Ketoconazole (NB! These medications are already generally advised contradicted against induring pregnancy)
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
1,520 participants (estimated)

Study arms

  • Experimental
    Sodium bicarbonate

    Participants receive oral sodium bicarbonate 4.26 gram once.

    Drug: Sodium bicarbonate

  • Placebo comparator
    Placebo

    Participants receive placebo once.

    Drug: Placebo

Interventions

06

What researchers measure

Primary outcomes

  1. Difference in incidence of assisted delivery

    Defined as a composite of emergency caesarean section and instrumental vaginal delivery

    Time frame: At birth

Secondary outcomes

  1. Difference in adverse neonatal outcome

    Composite of perinatal adverse outcomes within the first 7 days of life, including perinatal mortality and neonatal morbidity. Neonatal morbidity is defined as arterial umbilical cord pH \<7.10, resuscitation (bag and mask or intubation), hypoxic ischemic encephalopathy II-III, intracranial haemorrhage, neonatal seizures, meconium aspiration syndrome, and admission to a neonatal unit.

    Time frame: From birth until 7 days postpartum

  2. Difference in total oxytocin dose

    Administered intrapartum for augmentation.

    Time frame: Intrapartum

  3. Difference in duration of active labour

    From diagnosis of active labour until childbirth

    Time frame: Intrapartum

  4. Difference in birth experience

    Patient reported using Childbirth Experience Questionnaire (CEQ) which uses a 4-point Likert scale and higher scores indicate a more positive experience.

    Time frame: One month postpartum

  5. Difference in amniotic fluid lactate (AFL) concentration

    Collected in the labourroom and analysed externally. Attending clinicians will not know the AFL.

    Time frame: Measured at inclusion and two hours later.

  6. Difference in intra- or postpartum infection

    2 confirmed temperatures ≥38.5°C with epidural, ≥38 °C without epidural, or broad-spectrum antibiotics.

    Time frame: Intrapartum and until 7 days postpartum

  7. Difference in epidural analgesia

    As documented in the case records

    Time frame: Intrapartum

  8. Difference in number of women getting antibiotics during labour

    As documented in the case records.

    Time frame: Intrapartum

  9. Difference in postpartum blood loss

    Visual assessment estimated by the attending midwife or calculated using a weight if suspected postpartum haemorrhage.

    Time frame: From birth until 24 hours postpartum

  10. Difference in women receiving tocolytics used during labour

    Recorded in the case records

    Time frame: Intrapartum

  11. Difference in number of 3rd or 4th-degree perineal tears

    Assess by the midwife/doctor suturing the tear.

    Time frame: Within 2 hours after birth

07

Study locations

3 sites
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Start is estimated for Feb 2026; primary completion for Jan 2028, 23 months later.

Of 18 interventional studies with no phase under Dystocia, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 40. This study's planned 23 months is close to that.

How these figures are worked out, and which studies are left out of them.

Registered
Dec 22, 2025
First posted
Jan 7, 2026
StartEst.
Feb 1, 2026
Primary completionEst.
Jan 31, 2028
CompletionEst.
Jan 31, 2028
Last update
Jan 12, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jan 12, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07321379
Lead sponsor
Copenhagen University Hospital, Hvidovre
Collaborators
University of Copenhagen, Rigshospitalet, Denmark, Aarhus University Hospital, Copenhagen Trial Unit, Center for Clinical Intervention Research, University of Liverpool, University of Amsterdam
Responsible party
Nanna Maaløe (Associate Professor, Copenhagen University Hospital, Hvidovre) — Principal investigator
First posted
Jan 7, 2026
Start date
Feb 1, 2026 (estimated)
Primary completion
Jan 31, 2028 (estimated)
Completion
Jan 31, 2028 (estimated)
Last update
Jan 12, 2026

Study contacts

Nanna Maaløe, PI, PhD
Contact
nannam@sund.ku.dk
+4541271984
Nina Olsén Nathan, Co-PI, PhD
Contact
nina.olsen.nathan@regionh.dk
+4553670600
Nanna Maaløe, PhD
principal investigator · University of Copenhagen

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Studies of the drug tested here: Sodium Bicarbonate

Other studies in this condition

Dystocia →

Other studies from this sponsor

Copenhagen University Hospital, Hvidovre

Start the discussion