“It's natural that a woman might be skeptical about exercising while she's pregnant. So many changes are occurring in her body, it makes sense to have second thoughts about whether exercise might harm her or her unborn child. But it turns out that a thoughtful exercise program is good for both mother and child, according to medical experts. ‘We know that women who exercise during pregnancy have less chance of developing certain conditions like gestational diabetes,’ said Dr. Raul Artal, chairman of obstetrics, gynecology and women's health for the Saint Louis University School of Medicine. ‘Not only that, exercise maintains musculoskeletal fitness. Women can cope with the anatomical and physiological changes of pregnancy better when they're in good shape. They also tolerate labor better and recover more quickly from delivery.’ The baby also benefits. One study found that when an expectant mother works out, her fetus reaps cardiac benefits in the form of lower fetal heart rates. The American College of Obstetricians and Gynecologists recommends that pregnant women do at least 30 minutes of moderate exercise a day most days of the week. First, though, all women should consult a doctor to make sure it's OK. When choosing what sort of exercise to pursue, a woman should take into account the shape she was in before becoming pregnant, said Dr. Thomas Wang, a family practitioner for Kaiser Permanente in San Diego.