NCT07312227 · Massachusetts General Hospital
A Prospective Longitudinal Observational Cohort Study of Pregnant Women Residing at High Altitude in Bolivia
What this study is about
In this study, the investigators will follow two small cohorts of pregnant women: a group of participants of healthy women with uncomplicated pregnancies residing at high altitude, a control group of healthy women with uncomplicated pregnancies residing at sea level, 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.
View original scientific description
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, a control group of healthy women with uncomplicated pregnancies residing at sea level, 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.
Primary outcome measures
Pulmonary artery pressures
Time frame: Late pregnancy (35 ± 4 weeks gestation) and postpartum (6 ± 0.3 weeks)
Measurement will be performed by transthoracic echocardiography.
Echographic estimate of fetal weight
Time frame: Late pregnancy (35 ± 4 weeks gestation)
Nitric oxide metabolites
Time frame: Late pregnancy (35 ± 4 weeks gestation) and postpartum (6 ± 0.3 weeks) for maternal samples, at delivery (neonatal samples)
Measurement will be performed with a chemiluminescence assay.
RV remodeling echocardiography parameters
Time frame: Late pregnancy (35 ± 4 weeks gestation) and postpartum (6 ± 0.3 weeks)
Weight at birth
Time frame: At delivery
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- women delivering at participating hospitals at more than 3500 meters or women delivering at participating hospitals at sea level
- signed informed consent
Exclusion criteria
- preexisting cardiopulmonary pathologies (CHD, COPD, CKD, NYHA \> III)
Where
- Boston, Massachusetts
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Data: ClinicalTrials.gov · synced May 26, 2026 · Source of record for eligibility and locations