Hypertensive Disorder of Pregnancy · Observational Study

Microbial Metabolites and Outcomes of Pregnancy Study

ClinicalTrials.gov · August 3, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is a completed observational study designed to characterize trimethylamine-N-oxide (TMAO) levels across pregnancy trimesters and assess association with hypertensive disorders of pregnancy. No results are reported in this registry record; the study establishes a hypothesis and protocol but does not yet provide evidence of TMAO utility as a predictor of adverse pregnancy outcomes.

What was studied

Observational. Hypertensive Disorder of Pregnancy; Female; age from 18 Years; to 45 Years. Intervention: Pregnant persons. n = 201. 1 site: United States.

Key findings

Study enrolled 201 pregnant participants in a racially diverse US cohort Primary outcomes are TMAO levels measured at three timepoints: 10–14 weeks, 24–28 weeks, and delivery Hypothesis links maternal diet, gut microbiota, and TMAO to hypertensive disorders of pregnancy pathophysiology

Safety

Safety was not reported in the material analysed. Check the source before drawing any conclusion about harm.

Who this may help

This study is not yet ready for clinical translation. Once results are published, they will determine whether TMAO is a valid early-pregnancy biomarker for HDP risk stratification. Clinicians should await peer-reviewed publication of outcomes before considering TMAO measurement in pregnancy care.

Plain-language summary

This is a completed observational registry study with no published results reported; it establishes TMAO as a candidate biomarker in pregnancy but provides no outcome data to assess clinical utility.

Study design

As stated by the source record.

MethodsCohort model. Prospective time perspective. Primary outcome measures: TMAO level (assessed at 10-14 weeks gestation); TMAO level (assessed at 24-28 weeks gestation); TMAO level (assessed at Delivery)

DesignObservational

PopulationHypertensive Disorder of Pregnancy; Female; age from 18 Years; to 45 Years

Sample size201

InterventionPregnant persons

Setting1 site: United States

Reported figures

Quoted from the source exactly as published.

Sample size (actual enrollment)201

Primary outcome measure 1TMAO level at 10–14 weeks gestation

Primary outcome measure 2TMAO level at 24–28 weeks gestation

Primary outcome measure 3TMAO level at delivery

Clinical bottom line

Caveats

This registry record reports no results; outcome data have not been posted or published.
No control group or comparator population is described; single-arm design limits inference of causality or prediction strength.
Power calculation and statistical analysis plan are not stated in the registry record.
Temporal association between TMAO and HDP development is stated as hypothesis, not demonstrated.

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Observational prospective cohort design; no control arm or randomization.

Directness

moderate

Directly examines TMAO across pregnancy trimesters; relevance to HDP pathophysiology is mechanistic hypothesis, not proven.

Consistency

insufficient

Single-arm study; no comparison group or replication data provided in registry record.

Risk of bias

insufficient

Registry record does not describe blinding, allocation concealment, or outcome ascertainment procedures.

Sample adequacy

moderate

201 participants enrolled; adequate for hypothesis-generating biomarker characterization but no power calculation stated.

Source abstract

Registry record from ClinicalTrials.gov (NCT06362356). This is a study registration, not published results. Lead sponsor: The Cleveland Clinic. Recruitment status: COMPLETED. Study type: OBSERVATIONAL. Enrollment: 201 participants (ACTUAL). Conditions: Hypertensive Disorder of Pregnancy. Primary outcome measures: TMAO level , 10-14 weeks gestation; TMAO level , 24-28 weeks gestation; TMAO level , Delivery. Brief summary: Emerging data connect diet, the gut microbiota and its metabolites in cardiometabolic disease. Hypertensive disorders of pregnancy (HDP) are common and are a leading cause of maternal and neonatal morbidity. HDP likely share similar pathophysiology as cardiometabolic disease in non-pregnant people with a yet unrevealed role of diet and the gut microbiota, including systemic inflammation and endothelial dysfunction. Despite high biological plausibility that nutrition, the gut microbiota and its metabolites may play a role in health and disease in pregnancy, there is a paucity of data regarding these associations, thus limiting advancement of the field. Similar to the proposed pathogenesis for diet, gut microbiota and the microbial metabolite trimethylamine-N-oxide (TMAO) in cardiovascular disease, we hypothesize that the interplay between maternal diet, the gut microbiota and its associated microbial metabolites play a mechanistic role in HDP. We propose to test this hypothesis in a racially-diverse US cohort to determine association with adverse pregnancy outcomes, specifically future development of HDP. We propose to prospectively collect plasma and urine TMAO throughout pregnancy from a cohort of 200 pregnant participants. Through 1) characterizing plasma and urine TMAO levels across each trimester of pregnancy, and 2) assessment of this microbial metabolite as a predictor of development of HDP, we have the potential to identify a biomarker that would allow us to identify people at risk of HDP early in pregnancy and provide new opportunities for therapeutic interventions to improve maternal and neonatal outcomes.

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

Hypertensive Disorder of PregnancyNCT06362356The Cleveland Clinic