http://articles.mercola.com/sites/articles/archive/2002/12/21/exercise-part-thirteen.aspxPregnant women’s risk of delivering a baby during the first 37 weeks of pregnancy, known as preterm birth -- the primary cause of death among newborns in North America and Europe, may be reduced by vigorous activity such as jogging or bicycling. In aenCommunityServer 2008.5 SP1 (Build: 31106.3070)