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Oxytocin Receptor Expression in Pregnancy

Active, not recruiting
Conditions
Post-Abortion
Hemorrhage, Obstetric
Interventions
Other: Myometrial tissue sample collection
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.

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
Arm && Interventions
GroupInterventionDescription
2nd trimesterMyometrial tissue sample collectionSecond trimester myometrial tissue samples will be collected by core needle biopsy under ultrasound guidance in anesthetized women. Samples will be obtained primarily after second trimester surgical abortions or Dilation and Evacuation (D\&E) procedures as well as after rare gravid hysterectomies or after late second trimester cesarean deliveries.
1st trimesterMyometrial tissue sample collectionFirst trimester myometrial tissue samples will be collected by core needle biopsy under ultrasound guidance in anesthetized women. Samples will be obtained after first trimester surgical abortions or suction dilation and curettage (D\&C).
Non-pregnantMyometrial tissue sample collectionMyometrial tissue samples will be collected by core needle biopsy under ultrasound guidance in non-pregnant women undergoing gynecologic surgery under anesthesia for laparoscopic tubal ligation.
After term pregnancy (3rd trimester)Myometrial tissue sample collectionThird trimester myometrial tissue samples will be collected by core needle biopsy under ultrasound guidance in anesthetized women. Samples will be obtained at the time of cesarean delivery.
Primary Outcome Measures
NameTimeMethod
Oxytocin receptor expression30 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
NameTimeMethod
Function of myometrial oxytocin receptor30 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

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