Controlled exercise is a safe pregnancy intervention in mice.

During pregnancy, women often show a willingness to make positive lifestyle changes, such as smoking cessation, initiation of a vitamin regimen, improvement of their diet, and increases in their levels of exercise or physical activity. To study health outcomes in both pregnant mice and their offspring, we developed a model of controlled maternal exercise during mouse pregnancy. Female ICR and C57BL/6 mice underwent controlled wheel walking for 1 h daily, 5 d each week, at a speed of 6 m/min prior to and during pregnancy and nursing. Dam body weight, food consumption, pregnancy rates, litter size, pup weights and litter survival were used as markers of pregnancy success and were not significantly affected by controlled maternal exercise. The proposed exercise paradigm is a safe pregnancy intervention and can be explored further.