Oxytocin Receptor Expression in Pregnancy

Active, not recruiting

• Conditions: Post-Abortion; Hemorrhage, Obstetric

• Registration Number: NCT03907735
• Lead Sponsor: Oregon Health and Science University

Brief Summary

This study aims to determine when during gestation oxytocin receptor (OXTR) expression increases in the myometrium, which will contribute new insight to the management of obstetric hemorrhage and our understanding of normal and abnormal labor.

Detailed Description

In this descriptive study, we will obtain myometrial tissue samples by core needle biopsy under ultrasound guidance in anesthetized women immediately following surgical abortion and from controls, all of whom are undergoing a separate planned obstetric/gynecologic surgery. Tissue studies will be performed on these biopsy samples to examine oxytocin receptor expression and function.

Study Timeline

• Study First Submitted: 2019-04-05
• Study First Submitted QC: 2019-04-08
• Study First Posted: 2019-04-09
• Study Start: 2019-06-03
• Primary Completion: 2020-08-22
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-27
• Last Update Posted: 2025-05-31
• Study Completion: 2025-08

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: Female
• Target Recruitment: 30

Inclusion Criteria

• Women age 18-50
• Gestational age 14-26 weeks; or 6-13 weeks, 37-42 weeks, or non-pregnant (controls)
• Undergoing another planned surgical procedure with anesthesia (suction D&C, D&E, gravid hysterectomy, cesarean section, or laparoscopic tubal ligation)
• Able to give informed consent in English or Spanish

Exclusion Criteria

To optimize biopsy safety, we will exclude patients with anticipated difficult cases, that have additional risks of hemorrhage, or those with features that limit ultrasound visualization.

Increased risk of hemorrhage:

• Anemia (Hgb < 9)
• Anticoagulation, bleeding disorder, or coagulopathy
• Multiple gestation
• Infection or sepsis

For ultrasound-guided procedures:

• Obese, BMI ≥ 40
• History of ≥2 cesarean sections
• Large fibroids or uterine anomalies obstructing view
• Other poor visualization
• Thin myometrium < 1cm

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Oxytocin receptor expression	30 minutes	Measure of oxytocin receptor expression. Perform quantitative RT-PCR on mRNA extracted from biopsy samples obtained from subjects at the end of their procedure (within 30 minutes).

Secondary Outcome Measures

Name	Time	Method
Function of myometrial oxytocin receptor	30 minutes	Assessment of the function of the myometrial oxytocin receptor. Measure intracellular calcium in cultured myometrial cells after activating the receptor with oxytocin from biopsy samples obtained from subjects at the end of their procedure (within 30 minutes).

Trial Locations

Locations (1)

Oregon Health & Science University; 🇺🇸 Portland, Oregon, United States