Can living in high altitude affect pregnancy?

Colleen Julian, PhD

With our eternally blue skies and majestic mountain ranges, it should come as no surprise to those of us living in Colorado that Katherine Lee Bates penned the words that ultimately became “America the Beautiful” atop Pikes Peak overlooking Colorado Springs. In addition to its natural beauty, Colorado boasts the highest average altitude of any state, with approximately 250,000 people living above 8200 feet.

At high altitudes, the barometric pressure declines and, along with it, the level of oxygen in the air we breathe falls. For this reason, the high altitude of Colorado poses unique health challenges and provides a “natural laboratory” for us to learn more about how the human body responds and adapts to oxygen deprivation (or hypoxia). Given that hypoxia is a central component of several diseases including cardiopulmonary disease, stroke and cancer, improved understanding of the mechanisms by which we adapt to high altitude has important implications for biomedical research.

In the Julian Lab, we study how hypoxia affects pregnancy outcome. One of the greatest physiologic challenges of pregnancy is to maintain an adequate supply of oxygen to the developing fetus. This challenge is magnified at high altitude. At altitudes above 8000 feet, for example, babies weigh less and pregnant women are more likely to develop preeclampsia, a hypertensive disorder of pregnancy. In fact, the incidence of low birth weight in Colorado is consistently greater than the United States average, despite premature-delivery rates being well below the national mean.

Ultimately, our long-term goal is to integrate measures of maternal and fetal vascular function that are obtained during normal clinical visits with genomic data available through the Biobank to identify novel therapeutic targets to reduce the burden of hypoxia-associated disorders of pregnancy, including preeclampsia and fetal growth restriction.

Dr. Julian is an Assistant Professor at the University of Colorado, Department of Medicine studying the molecular and physiologic regulation of fetal growth.