Physical activity during pregnancy - past and present.

The possible implications of physical activity during the period of pregnancy have been much debated over recent decades. This brief appraisal integrates knowledge from an array of position papers, systematic reviews, meta-analyses, and recommendations provided by specialty board committees. The medical community is becoming more and more aware of the beneficial effects of mild and moderate physical activity on the mother and the fetus, including improved clinical correlates of subsequent vaginal delivery, as contrasted to the clearly unbeneficial effects of a sedentary lifestyle.