I ran up until a couple days before giving birth and I saw lots of surprised looks from people as I jogged by with my expanded belly. But hundreds of studies have shown physical activity to be not only safe, but beneficial, for expectant mothers. Exercise can help keep pregnancy weight gain in check, prevent gestational diabetes and pregnancy-induced hypertension, and possibly reduce length of labor.

If you're expecting and you ran before you got pregnant, James Pivarnik, Ph.D., an expert from the American College of Sports and Medicine, recommends the following:

• Consult your healthcare provider to make sure your running plan is safe and specific for your needs. Every woman and every pregnancy is different.
• Aim to simply maintain your fitness level with moderate, frequent exercise. You shouldn't try to overexert yourself to reach a peak fitness level or train for a race.
• Don't ignore warning signs if they occur while running, such as vaginal bleeding, cramping, excessive nausea, lightheadedness, or extreme headaches. Consult your doctor immediately if any of those problems arise.

Related links:

• 10 Reasons to Exercise During Pregnancy
• Pregnancy Exercise and Fitness