The practice of yoga during pregnancy seems to improve birth weight and reduce prematurity and overall complications, Indian researchers report.

Dr. Shamanthakamani Narendran, from the Vivekananda Yoga Research Foundation in Bangalore, and colleagues studied 169 pregnant women trained in the integrated approach to yoga and in 166 “controls” who received routine prenatal care.

The yoga training included various loosening exercises, postures (“asanas”), relaxation, deep breathing exercises (“pranayamas”), and meditation, which was practiced for 1 hour daily.

Fourteen percent of deliveries were premature in the yoga group compared with 29 percent in the controls. Rates of pregnancy-related high blood pressure were also lower in the yoga group, the researchers report in the Journal of Alternative and Complimentary Medicine.

“The exact role of yoga is unclear at present,” said co-author Dr. Vivek Narendran of Cincinnati Children’s Hospital and Medical Center in Ohio.

He said possible mechanisms whereby yoga improves pregnancy outcomes include increased blood flow to the placenta, decreased transfer of maternal   stress hormones, and decreased premature release of hormones that trigger the onset of labor.

“Given the larger picture of multiple failed attempts to reduce low birth weight and prematurity globally in the last decade,” Dr. Narendran commented, “we provide preliminary data for the first time, to support a simple potential intervention, particularly in India, to improve pregnancy outcomes.”

SOURCE: Journal of Alternative and Complimentary Medicine, April 2005.