A Prospective Longitudinal Observational Cohort Study of Pregnant Women Residing at High Altitude in Bolivia

NCT ID: NCT07312227

Last Updated: 2025-12-31

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 20 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2026-02-28
• Study Completion Date: 2027-02-28

Brief Summary

In this study, the investigators will follow two small cohorts of pregnant women: a cohort of healthy women with uncomplicated pregnancies residing at high altitude, and a hospitalized cohort of symptomatic women with pregnancies complicated by obstetric conditions (e.g., preeclampsia), to characterize differences in cardiopulmonary adaptation and nitric oxide (NO) pathway expression at elevations >3,500 m throughout pregnancy and into the postpartum period. The investigators aim to investigate right-sided cardiac impairment induced by chronic hypobaric hypoxemia, its effects on fetal growth, and the potential contribution of cardiovascular nitric oxide depletion to obstetric complications such as preeclampsia, pulmonary arterial hypertension, and right ventricular dysfunction.

Detailed Description

To investigate cardiac impairment, the investigators will perform transthoracic echocardiography in all enrolled pregnant women and infants, with a focus on right-sided cardiac anatomy and function, including pulmonary artery pressures, right ventricular thickness, right ventricular systolic performance, and indices of pulmonary vascular load.

To investigate the effects of hypobaric hypoxia on fetal growth, the investigators will measure intrauterine and post-delivery growth parameters, assess placental weight and histologic features, and correlate these findings with maternal oxygenation status and altitude exposure.

To assess nitric oxide production and consumption, the investigators will quantify nitric oxide-related metabolites (NO metabolomics) in maternal blood, umbilical cord blood, and placental tissue in both cohorts, and correlate these biomarkers with preeclampsia, pulmonary arterial hypertension, and right ventricular dysfunction. The investigators will also assess flow-mediated dilation in symptomatic and asymptomatic participants and relate these measures of endothelial function to pulmonary vascular and obstetric outcomes.

Conditions

Hypertensive Disorder of Pregnancy; Pulmonary Arterial Hypertension; Intrauterine Growth Restriction

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Healthy pregnant women residing at high altitude

Women with uncomplicated pregnancy.

No interventions assigned to this group

Symptomatic pregnant women residing at high altitude

Women with pregnancy complicated by obstetric conditions such as hypertensive disorders of pregnancy. Hospitalized.

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• singleton pregnancy
• women delivering at participating hospitals at more than 3500 meters
• signed informed consent

Exclusion Criteria

• multiple pregnancy
• preexisting cardiopulmonary pathologies (CHD, COPD, CKD, NYHA > III)

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 45 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

Massachusetts General Hospital

OTHER

Sponsor Role: lead

Responsible Party

Lorenzo Berra, MD

PI

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Lorenzo Berra, MD

Role: PRINCIPAL_INVESTIGATOR

Massachusetts General Hospital

Central Contacts

Lorenzo Berra, MD

Role: CONTACT

Phone: 617-726-3030

Email: lberra@mgh.harvard.edu

Andrea Bolchini, MD

Role: CONTACT

Phone: 617-216-5124

Email: abolchini@mgh.harvard.edu

Other Identifiers

PregHigh

Identifier Type: -

Identifier Source: org_study_id