Recruiting

Carbetocin

Sponsor:

Samuel Lunenfeld Research Institute, Mount Sinai Hospital

Code:

NCT06930391

Conditions

Postpartum Hemorrhage (Primary)

Eligibility Criteria

Sex: Female

Age: 18 - 40

Healthy Volunteers: Accepted

Interventions

Oxytocin

Carbetocin

Calcium

Study Details

Brief summary:

Postpartum hemorrhage (PPH) continues to be an increasing problem globally. Uterotonics play an essential role in the pharmacological management of uterine atony. Carbetocin, a long acting analog of oxytocin has been recommended as a first line uterotonic for PPH prophylaxis at cesarean delivery. Considering many woman have associated comorbidities and are at high risk of PPH, finding alternative pharmacological agents is essential. Calcium is a key factor for myometrial contractions and calcium blood levels can be low at the end of pregnancy. Both hypocalcemia and hypercalcemia could lead to a decrease in myometrial contractions. It is already been demonstrated that in both desensitized and naïve myometrium, normocalcemia provides a better uterine tone compared to hypo and hypercalcemia when oxytocin is given as the first uterotonic drug.

Currently, the role of extracelullar calcium in carbetocin- induced contractility is unknown. This will be the first ex vivo study to test the effects of extracellular calcium on oxytocin pretreated and naive myometrium. The results of this study will provide evidence on the use of this safe drug in clinical practice, particularly in women with labour arrest, and provide alternative pharmacological strategies to both prevention and treatment of PPH, thus improving our clinical practice.

The investigators hypothesize that extracellular normocalcemia would provide superior carbetocin-mediated contractility in both naive and oxytocin-pretreated myometrium compared with hypercalcemia and hypocalcemia.

Conditions

Postpartum Hemorrhage (Primary)

Study ID

NCT06930391

Start date

Sep 15, 2025

Status verified date

Sep, 2025

Completion date

Jun, 2026

Anticipated

Primary completion date

Jun, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 18 - 40

Healthy Volunteers: Accepted

Inclusion Criteria:

  • non-laboring women with gestational age between 37 to 41 weeks
  • not exposed to exogenous oxytocin, scheduled for a primary or first repeat cesarean delivery under neuraxial anesthesia.

Exclusion criteria:

  • patients requiring general anesthesia
  • more than 1 previous cesarean delivery
  • history of uterine atony
  • emergency cesarean section in labor
  • patients using medications that could affect myometrial contractility such as nifedipine, labetalol, or magnesium sulphate.
  • patients with any condition of predisposing to uterine atony and postpartum hemorrhage, such as abnormal placentation, multiple gestation, severe preeclampsia, macrosomia, polyhydroamnios, large uterine fibroids, chorioamnionitis, previous history of postpartum bleeding.

Study Design

Enrollment

40 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

active comparator: Calcium 1.25nM with NO oxytocin pre-exposure

Dose-response testing with 1.25nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with NO oxytocin pre-exposure

active comparator: Calcium 2.5nM with NO oxytocin pre-exposure

Dose-response testing with 2.5nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with NO oxytocin pre-exposure

active comparator: Calcium 5.0nM with NO oxytocin pre-exposure

Dose-response testing with 5.0nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with NO oxytocin pre-exposure

active comparator: Calcium 1.25nM with oxytocin pre-exposure

Dose-response testing with 1.25nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with oxytocin pre-exposure

active comparator: Calcium 2.5nM with oxytocin pre-exposure

Dose-response testing with 2.5nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with oxytocin pre-exposure

active comparator: Calcium 5.0nM with oxytocin pre-exposure

Dose-response testing with 5.0nM calcium chloride, and increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M, with oxytocin pre-exposure

Interventions

Oxytocin

Oxytocin 10-5M will be added to 3 groups of myometrial strips for 2 hours to induce desensitization.

Carbetocin

Increasing concentrations of carbetocin in a pattern of 1 log molar increase every 10 min, from 10-10 M to 10-5 M

Calcium

Calcium chloride in the following concentrations:1.25mM, 2.5mM and 5.0mM.

Primary outcome measure

  • Motility index [ Time Frame: 4 hours ]

Central Contacts and Locations

Central contacts

Mrinalini Balki, MD

416-586-480mrinalini.balki@uhn.ca

Locations

Mount Sinai Hospital

Recruiting

Toronto, Ontario, Canada, M5G1X5

Contacts

Mrinalini Balki, MD

416-586-4800mrinalini.balki@uhn.ca

Principal Investigator:

Mrinalini Balki, MD

More Information

Sponsor

Samuel Lunenfeld Research Institute, Mount Sinai Hospital

Last update posted

Sep 24, 2025

Last verified

Sep, 2025

Keywords

  • carbetocin
  • calcium
  • uterine contraction
  • cesarean delivery

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Samuel Lunenfeld Research Institute, Mount Sinai Hospital on 2025-09-24.