Potential breakthrough for low birth weight babies

Wednesday May 20, 2009 (foodconsumer.org) -- A new study shows that Andean women are able to deliver more oxygen to their fetuses at high altitudes than are women of European descent. This could lead researchers to discover practical ways to increase uterine blood flow to high risk fetuses and/or help pregnancies complicated by reduced fetal growth.

The American Journal of Physiology —Regulatory, Integrative and Comparative Physiology is reporting the research in its current issue. While all babies born at high altitude are at a greater risk for low birth weight, those of Andean descent are still 9 ounces larger than those of European descent.

The determining factor in the higher Andean birth weight appears to be the amount of oxygen delivered by the uterine artery. As opposed to European women, the Andeans are able to deliver more oxygen and blood through the artery to their fetuses. Genetic adaptation has evolved over the centuries to help Andean women overcome the low oxygen environment in which their babies develop.

The study narrowed down some of the most critical factors affecting birth weight:

• The amount of oxygen being delivered through the uterine artery
• The amount of oxygen being delivered through the placenta

In tandem, the amount of oxygen and nutrients that are able to reach the baby through both the uterine artery and the placenta are major determinants with regards to birth weight.

The study is significant because it can help doctors to determine how to assist women whose pregnancies are complicated by low birth weight, or whose babies are not getting sufficient oxygen through the uterine artery. Low weight babies are subject to a plethora of complications that full term and heavier babies are able to completely bypass.

(By Rachel Stockton, and edited by Heather Kelley)