Uterine Artery Doppler Changes

Uterine Artery Doppler Changes From the Second Trimester of Pregnancy to the Postpartum Period in a Group of High Risk Women

In uncomplicated pregnancies, the uterine spiral arteries undergo a series of structural changes that result in a low resistance in the uterine arteries as pregnancy progresses.

In many pregnancies complicated with preeclampsia, growth restriction and other placental related complication, the described change does not occur. In pregnancies at high risk for placental complications, doppler measurement of Uterine artery flow has been shown to be a reliable predictor of complications.

Postpartum there is a reversal of vascular changes seen in normal pregnancies. It is unclear if there is a full reversal of these changes in complicated pregnancies with abnormal flow during pregnancy.

The investigators hypothesize that Doppler uterine artery measurements after complicated pregnancies will show some abnormality compared to doppler measurements following uncomplicated pregnancies.

Study Overview

• Status: Unknown
• Conditions: Uterine Artery Flow
• Intervention / Treatment: Other: Post-partum Doppler ultrasound

Detailed Description

The postpartum reversal of pregnancy-related changes in uterine artery (UA) flow is not well documented.

While long-term vascular changes have been noted in women with prior preeclampsia (PE), and in a dose- dependent manner, long-term changes to UA vascular resistance following PE have not been analyzed. Moreover, regardless of whether they experienced PE or intrauterine growth restriction (IUGR), it is not known if women with elevated UA pulsatility index (PI) in mid-pregnancy have higher UA well after pregnancy, compared to women whose UA PI was normal in mid-pregnancy.

The investigators propose to evaluate if UA flow remains abnormally high postpartum in women who had elevated UA flow mid-pregnancy, compared to women whose UA flow was normal in mid-pregnancy.

This is an observational prospective study. The study recruits women that have recently delivered and have undergone a Uterine Doppler ultra sound (US) during the second trimester of their pregnancy. Eligible women will undergo one post-partum ultrasound examination.

• Study Type: Observational
• Enrollment (Anticipated): 32

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5B 1W8
      • St. Michael's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Probability Sample

Study Population

Women with singleton pregnancies.

Description

Inclusion Criteria:

• Women who underwent UA Doppler assessment at 18-22 weeks gestation.
• Viable singleton pregnancy at the time of UA Doppler assessment at 18-22 weeks gestation.
• Is at least 6 weeks postpartum following a livebirth of the aforementioned pregnancy
• Not pregnant at time of post-partum UA Doppler assessment

Exclusion Criteria:

• Women will be excluded if they do not meet the above criteria

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Normal second trimester Doppler; This group consists of women who had normal doppler ultrasound results at second trimester	Other: Post-partum Doppler ultrasound; Participants will undergo one uterine artery Doppler ultrasound at 6 weeks post-partum.
Abnormal second trimester Doppler; This group consists of women who had abnormal doppler ultrasound results at second trimester	Other: Post-partum Doppler ultrasound; Participants will undergo one uterine artery Doppler ultrasound at 6 weeks post-partum.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in uterine artery flow	Uterine artery flow measurements during pregnancy and after, as measured by Doppler ultrasound	2nd trimester (between 13 to 22 weeks gestation) and 6 weeks post-partum

Collaborators and Investigators

• Sponsor: Unity Health Toronto

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2017
• Primary Completion (Anticipated): September 1, 2022
• Study Completion (Anticipated): September 1, 2022

Study Registration Dates

• First Submitted: February 13, 2017
• First Submitted That Met QC Criteria: February 22, 2017
• First Posted (Actual): February 27, 2017

Study Record Updates

• Last Update Posted (Actual): October 20, 2020
• Last Update Submitted That Met QC Criteria: October 18, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: 16-035

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No