A: It's quite common not to notice your baby moving when you're engaged in exercise. Babies go through sleep and wake cycles. It's possible that your movements soothe your baby and help him sleep. Or, your baby may be active but your own physical activity makes it difficult to perceive these fetal movements.

As long as you drink plenty of fluids, you're not out of breath when you exercise, and you feel your baby moving at other times of the day, you won't be harming your baby by exercising. In fact, exercising an average of 30 minutes or more each day is recommended for healthy pregnancies. If you're concerned about your baby's activity level in general, you can do kick counts on a daily basis. After eating a meal, lie on your left side and count how long it takes for your baby to move 10 times. If this takes more than an hour, call your doctor.

You should be aware that there are some conditions in pregnancy that make it unwise to engage in a standard exercise program. The American College of Obstetricians and Gynecologists advises caution if you have any of the following conditions: pregnancy induced high blood pressure; preterm labor with this pregnancy or a previous one; an incompetent cervix; vaginal bleeding in the second or third trimester; inadequate fetal growth; or active cardiac, vascular or pulmonary disease.