According to recent research published in the American Journal of Obstetrics and Gynecology that studied the effects of exercise during pregnancy, the amount and intensity of exercise can affect both maternal and fetal weight.

Seventy-five moms who already exercised regularly five times a week were assigned to one of three exercise groups. One third of the moms initially did 20 minutes of aerobic exercise and increased the duration of the exercise session over the course of their pregnancies; one third of the moms initially did 60 minutes and then decreased the duration of their exercise sessions; and one third of the moms exercised for 40 minutes throughout the entire pregnancy.

The results? The babies of moms who worked out intensely in mid- or late pregnancy were significantly lighter and had less body fat than infants born to the moderate exercisers. However, these lighter infants weren't small enough to be at risk for medical or developmental problems. In addition working out regularly during pregnancy controlled the mother’s weight in some cases - women who exercised vigorously during early pregnancy and then reduced the amount of exercise as pregnancy progressed weighed more and had heavier placentas than women in the other groups.

Exercise during pregnancy can be beneficial for babies and moms, and can help moms control weight gain during pregnancy. Talk to your obstetrician for tips and suggestions if you intend to exercise during pregnancy.

Related information Weight Management Center

Sources:  Clapp JF, Kim H, Burciu B, Schmidt S, Petry K, Lopez B. Continuing regular exercise during pregnancy: Effect of exercise volume on fetoplacental growth. American Journal of Obstetrics and Gynecology, January 2002, Vol. 186, No. 1(Abs.).