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Active, Not Recruiting

NCT Number: NCT06352775

Calcium Carbonate on Labor Induction

The investigators aim to evaluate the safety and efficacy of administering calcium carbonate to laboring participants undergoing labor inductions. The investigators hypothesize that calcium carbonate is a low-risk preventative measure to decrease oxytocin induction time and dosage, decrease the rate of labor dystocia, decrease the rate of cesarean deliveries, and demonstrate no differences in maternal or neonatal safety outcomes.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

Pregnancy Dystocia Female Urogenital Diseases and Pregnancy Complications Obstetric Labor Complications Pregnancy Complications Urogenital Diseases Uterine Contraction

Age range

18 year and older

Sex eligibility

Female

Study type

Interventional

Phase

Not applicable

Primary location

Aurora Sinai Medical Center

Milwaukee, Wisconsin, 53233, United States

About this study

The investigators plan to assess (1) duration of induction with oxytocin administration, (2) rate of labor dystocia/failed induction, (3) rate of cesarean section, and (4) maternal/neonatal safety. Currently, calcium carbonate is used by clinicians in patients with varying characteristics, at varying doses, and at various times in their labor process based on their professional preference and experience. The investigators will implement a standardized treatment protocol for calcium carbonate use within a defined patient population who voluntarily agree to prospectively receive the intervention and then analyze predetermined safety and efficacy outcomes in comparison to a historical cohort of patients meeting the criteria for the defined patient population who did not have any documented calcium carbonate use during labor.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adult laboring patients ( ≥ 18 years of age)
  • Able to speak and read English or Spanish (for historical cohort, preferred language should be English or Spanish)
  • Singleton gestation
  • Greater ≥ 37 weeks gestation in vertex presentation
  • Present for induction of labor inclusive of medical indication, elective indication at greater than 39 weeks gestation, trial of labor after cesarean
  • Receive standard-dose oxytocin during induction

Exclusion criteria

  • Participants will be excluded from the study if they do not meet the above inclusion criteria or they will be further excluded under the following circumstances:
  • Known need for cesarean section prior to induction of labor
  • Known allergy to calcium carbonate
  • Known contraindication to taking calcium carbonate including renal calculus, high urine calcium levels, elevated serum calcium, low serum phosphate, achlorhydria, or suspected digoxin toxicity.
  • Inability to tolerate oral intake (i.e., nausea/vomiting)
  • Need to be nothing by mouth (NPO)

Treatment and study plan

Calcium Carbonate

Dietary Supplement

We will be using it in routes and doses consistent with its approved uses. Per the drug label information for Calcium Carbonate USP 500 mg found in the US National Library of Medicine, adults may take 2-4 tablets as symptoms occur and if pregnant to not exceed 10 tablets in 24 hours. Therefore, using a dosing of 500mg every 4 hours will be well below that guidance. When both cervical ripening has been completed and the oxytocin administration begins, the calcium carbonate treatment group will be given calcium carbonate 500mg every 4 hours (not to exceed 10 tablets in 24 hours) until they deliver.

Primary outcomes

  1. Duration of induction time

    Time frame: During the intervention (time from duration of induction with oxytocin start to delivery)

    Participants in the treatment group will have a shorter duration of induction with oxytocin than those in the retrospective historical control group.

  2. Rate of labor dystocia

    Time frame: During the intervention (measured from time of induction to delivery)

    Participants in the treatment group will have a lower rate of labor dystocia than those in the retrospective historical control group.

Secondary outcomes

  1. Rate of cesarean deliveries

    Time frame: During the intervention (measured from time of induction to delivery)

    Participants in the treatment group will have a lower rate of cesarean deliveries than those in the retrospective historical control group.

  2. Total amount of oxytocin after cervical ripening

    Time frame: During the intervention (time on oxytocin after cervical ripening completed to delivery)

    Participants in the treatment group will receive a lower amount of oxytocin than those in the retrospective historical control group.

  3. Gastrointestinal side effects

    Time frame: During the intervention (time on calcium carbonate to delivery)

    Participants in the treatment group will describe gastrointestinal side effects.

  4. Blood loss

    Time frame: Time from delivery to 24 hours of birth

    Participants in the treatment group will experience less blood loss than those in the retrospective historical control group.

  5. Rate of postpartum hemorrhage (>/= 500mL)

    Time frame: Time from delivery to 24 hours of birth

    Participants in the treatment group will experience less postpartum hemorrhage than those in the retrospective historical control group.

  6. Neonatal composite adverse outcomes

    Time frame: Immediately after the birth until the time of discharge, an average of 3 days

    Neonates of participants in the treatment group will have comparable composite adverse outcomes to those born to participants in the retrospective historical control group.

Sponsors and collaborators

Lead sponsor

Wake Forest University Health Sciences

Other

Registry information

Official study title

The Effect of Calcium Carbonate on Labor Induction: A Pilot Study

Important dates

Study start
2024
Primary completion
2026
Study completion
2026
First posted
Apr 8, 2024
Registry last updated
Nov 21, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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