CClinicalTrials.gg
TerminatedNCT03298802Updated Jul 14, 2026Results posted

Postpartum Management of Hypertension in Pregnancy With Hydrochlorothiazide

A Phase 3 interventional study of Hydrochlorothiazide 50mg Tablet and Placebo Tablet in Pre-Eclampsia, Gestational Hypertension and Superimposed Pre-Eclampsia, sponsored by The University of Texas Medical Branch, Galveston. Terminated at 2 sites in United States. Open to female participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-07-14.

Sponsored by The University of Texas Medical Branch, Galveston · Phase 3, Interventional, and Prevention

Why this study was terminated
Futility of the study
Phase
Phase 3
Study type
Interventional
Enrollment
453
Allocation
Randomized
Ages
18 Years to 50 Years
Sex
Female
01

Study summary

Postpartum prophylactic HCTZ administration for prevention and relapse of preeclampsia or gestational hypertension.

Read the detailed description

To evaluate effectiveness of hydrochlorothiazide prophylaxis on prophylaxis, prevention and relapse of preeclampsia or gestational hypertension on readmission rates, need for additional antihypertensive therapy and number of triage visits.

02

Conditions studied

  • Pre-Eclampsia
  • Gestational Hypertension
  • Superimposed Pre-Eclampsia
  • Hypertension, Pregnancy-Induced
  • Postpartum Pregnancy-Induced Hypertension
  • Postpartum Preeclampsia

Keywords

  • readmission
  • triage visit for pregnancy related hypertension
  • hydrochlorothiazide
03

Who can participate

Ages eligible
18 Years to 50 Years
Sexes eligible
Female
Accepts healthy volunteers
No

Inclusion criteria

  • Maternal age ≥ 18 years and \<50 years.
  • Diagnosis of gestational hypertension* or preeclampsia\^ at any time during pregnancy, labor or postpartum.

    • defined as isolated systolic BP of 140 mm Hg or greater, a diastolic BP of 90 mm Hg or greater, or both) or \^ defines as new-onset hypertension plus new-onset proteinuria, or in the absence of proteinuria, preeclampsia is diagnosed as hypertension in association with thrombocytopenia (platelet count less than 100,000/microliter), impaired liver function (elevated blood levels of liver transaminases to twice the normal concentration), the new development of renal insufficiency (elevated serum creatinine greater than 1.1 mg/dL or a doubling of serum creatinine in the absence of other renal disease), pulmonary edema, or new-onset cerebral or visual disturbances.)

Exclusion criteria

Exclusion Criteria:

  • Subject requiring antihypertensive therapy at time of screening.
  • Planned discharge with oral anti-hypertensive medication.
  • Contraindication to hydrochlorothiazide (advanced renal failure or anuria, hypersensitivity to sulfonamides).
  • Subject not able to follow up postpartum.
  • Lactose intolerance.
  • Pre-gestational diabetes.
04

Study design

Phase
Phase 3
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Care provider, Investigator)
Enrollment
453 participants (actual)

Study arms

  • Active comparator
    Hydrochlorothiazide 50mg Tablet

    Hydrochlorothiazide 50 mg per os once daily as soon as the subjects can tolerate sips of water after delivery and for a total of fourteen days postpartum.

    Drug: Hydrochlorothiazide 50mg Tablet

  • Placebo comparator
    Placebo Tablet

    Placebo per os once daily as soon as the subjects can tolerate sips of water after delivery and for fourteen days postpartum

    Drug: Placebo Tablet

Interventions

  • DrugHydrochlorothiazide 50mg Tablet

    Hydrochlorothiazide 50 mg per os once daily as soon as the subjects can tolerate sips of water after delivery and for a total of fourteen days postpartum.

    Also known as: HydroDIURIL, Microzide, Esidrix, Oretic

  • DrugPlacebo Tablet

    Placebo per os once daily as soon as the subjects can tolerate sips of water after delivery and for a total of fourteen days postpartum

    Also known as: sugar pill

05

What researchers measure

Primary outcomes

  1. Number of Participants Required Re-Admission or Triage Visit

    Any participants who had a visit to the hospital during the 1-6 weeks postpartum.

    Time frame: 1-6 weeks postpartum

  2. Number of Participants That Need Additional Antihypertensive Therapy

    Number of participants requiring additional antihypertensive agents in 1-6 weeks postpartum window

    Time frame: 1-6 weeks postpartum

Secondary outcomes

  1. Length of Hospital Stay

    Days that participants required to be in-house in the postpartum period

    Time frame: 1-6 weeks postpartum

  2. Total Additional Doses of Anti-hypertensive Therapy

    Number of participants that receive one additional doses in the 1-6 weeks postpartum

    Time frame: 1-6 weeks postpartum

  3. Elevation of Blood Pressure >150/90

    Number of participants that have a blood pressure greater than 150/90 in the 1-6 weeks postpartum window

    Time frame: 1-6 weeks postpartum

  4. Severe Composite Maternal Morbidity

    Number of participants with any of the following: ICU admission, HELLP syndrome, eclampsia, stroke, renal failure, pulmonary edema, cardiomyopathy or maternal death.

    Time frame: 1-6 weeks postpartum

  5. Adverse Events

    Allergic reactions (anaphylaxis, angioedema, skin rashes including Stevens Johnson and Toxic Epidermal necrolysis)

    Time frame: 1-6 weeks Postpartum

Other outcomes

  1. Use of Resources

    Number of participants that had additional Hospital Stay, Postpartum Clinic or Emergency room visit, Need for Imaging or other Invasive Procedures within 4-6 weeks of delivery, 4-6 weeks postpartum.

    Time frame: 1-6 weeks postpartum

06

Results

Posted Jun 24, 2026
Limitations and caveats
The study began in 2016 and underwent multiple Principal Investigator (PI) transitions. All study data have now been fully identified, verified, and reported in this final dataset.

Participant flow

Participant flow — Overall Study
MilestoneHydrochlorothiazide 50mg TabletPlacebo Tablet
Started201199
Completed196196
Not completed53

Outcome measures

PrimaryNumber of Participants Required Re-Admission or Triage Visit

Any participants who had a visit to the hospital during the 1-6 weeks postpartum.

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Number of Participants Required Re-Admission or Triage Visit
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Number of Participants Required Re-Admission or Triage Visit310
PrimaryNumber of Participants That Need Additional Antihypertensive Therapy

Number of participants requiring additional antihypertensive agents in 1-6 weeks postpartum window

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Number of Participants That Need Additional Antihypertensive Therapy
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Number of Participants That Need Additional Antihypertensive Therapy66
SecondaryLength of Hospital Stay

Days that participants required to be in-house in the postpartum period

Time frame:
1-6 weeks postpartum
Reported as:
Mean · days
Length of Hospital Stay
daysHydrochlorothiazide 50mg TabletPlacebo Tablet
Length of Hospital Stay2.25 ± 0.932.18 ± 0.57
SecondaryTotal Additional Doses of Anti-hypertensive Therapy

Number of participants that receive one additional doses in the 1-6 weeks postpartum

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Total Additional Doses of Anti-hypertensive Therapy
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Total Additional Doses of Anti-hypertensive Therapy66
SecondaryElevation of Blood Pressure >150/90

Number of participants that have a blood pressure greater than 150/90 in the 1-6 weeks postpartum window

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Elevation of Blood Pressure >150/90
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Elevation of Blood Pressure >150/902115
SecondarySevere Composite Maternal Morbidity

Number of participants with any of the following: ICU admission, HELLP syndrome, eclampsia, stroke, renal failure, pulmonary edema, cardiomyopathy or maternal death.

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Severe Composite Maternal Morbidity
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
ICU admission00
HELLP syndrome00
Eclampsia00
Maternal Death00
Cardiomyopathy00
Pulmonary edema00
Renal failure00
Stroke00
SecondaryAdverse Events

Allergic reactions (anaphylaxis, angioedema, skin rashes including Stevens Johnson and Toxic Epidermal necrolysis)

Time frame:
1-6 weeks Postpartum
Reported as:
Count of participants · Participants
Adverse Events
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Anaphylaxis00
Angioedema00
Skin Rashes Including Stevens Johnson00
Skin Rashes Including Toxic Epidermal Necrolysis00
Other pre-specifiedUse of Resources

Number of participants that had additional Hospital Stay, Postpartum Clinic or Emergency room visit, Need for Imaging or other Invasive Procedures within 4-6 weeks of delivery, 4-6 weeks postpartum.

Time frame:
1-6 weeks postpartum
Reported as:
Count of participants · Participants
Use of Resources
ParticipantsHydrochlorothiazide 50mg TabletPlacebo Tablet
Additional Hospital Stay10
Clinic or Emergency room visit00
Need for Imaging00
Need for other Invasive Procedures00

Adverse events

Collected over 1-6 weeks postpartum. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Hydrochlorothiazide 50mg Tablet0/196 (0%)1/196 (0.5%)1/196 (0.5%)
Placebo Tablet0/196 (0%)0/196 (0%)1/196 (0.5%)
Most frequent serious events
Most frequent serious events
EventHydrochlorothiazide 50mg TabletPlacebo Tablet
Hospital AdmissionGastrointestinal disorders1/1960/196
Most frequent other events
Most frequent other events
EventHydrochlorothiazide 50mg TabletPlacebo Tablet
Patient diagnosed with Pyelonephritis and urosepsisRenal and urinary disorders1/1960/196
Allergic ReactionImmune system disorders0/1961/196

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Hydrochlorothiazide 50mg TabletPlacebo TabletTotal
<=18 years000
Between 18 and 65 years201199400
>=65 years000
Sex: Female, Male
Sex: Female, Male(Participants)Hydrochlorothiazide 50mg TabletPlacebo TabletTotal
Female201199400
Male000
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Hydrochlorothiazide 50mg TabletPlacebo TabletTotal
American Indian or Alaska Native101
Asian134
Native Hawaiian or Other Pacific Islander101
Black or African American302151
White168175343
More than one race000
Unknown or Not Reported000
Region of Enrollment
Region of Enrollment(participants)Hydrochlorothiazide 50mg TabletPlacebo TabletTotal
United States201199400
07

Study locations

2 sites
  • St. David's North Austin Medical Center
    Austin, Texas 78758, United States
  • University of Texas Medical Branch
    Galveston, Texas 77555, United States
08

References and documents

Study documents

  • Protocol and statistical analysis plan · May 22, 2023

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

09

Registry details

Key details

Study ID
NCT03298802
Lead sponsor
The University of Texas Medical Branch, Galveston
Responsible party
Sponsor
First posted
Oct 2, 2017
Start date
Nov 21, 2017
Primary completion
Apr 22, 2025
Completion
Apr 22, 2025
Results posted
Jun 24, 2026
Last update
Jul 14, 2026

Study contacts

Benjamin Bush, M.D.
principal investigator · UTMB

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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