Most women can, and should, engage in mild to moderate exercise during pregnancy. Exercise can help you stay in shape as well as prepare your body for labor and delivery. However, talk with your health care provider before you begin exercising during pregnancy.

Walking, swimming and cycling are all excellent forms of exercise during pregnancy. Strengthening exercises are appropriate using light weights. You also may want to consider a prenatal exercise class. Instructors can illustrate safe and effective floor exercises.

Benefits of Exercise During Pregnancy

Exercise during pregnancy can:

• Improve strength and stamina
• Strengthen muscles in preparation for labor and delivery
• Help to resolve constipation
• Improve fitness
• Relieve back pain
• Increase flexibility
• Improve your mood
• Improve your sleep

Physical Changes to Keep in Mind

At the same time, there are a number of key points to keep in mind while you exercise:

• Your balance and center of gravity will change as your baby grows larger
• You may feel more short of breath as oxygen demands change
• Blood volume increases so your heart's workload increases
• Pregnancy hormones can cause ligaments to loosen and stretch

How to Exercise Safely

Whether you are pregnant or not, it always is important to warm up and cool down when exercising. Take five to 10 minutes at the beginning of your exercise session to gradually warm up your muscles and prepare your body. When you finish your exercise session, gradually slow down rather than stopping abruptly. The warm-up and cool-down periods can involve the same form of activity as your exercise — for example, walking or swimming — but should be performed at a lower intensity and slower speed.

Other important tips include:

• Dress for the weather
• Wear the appropriate clothing, such as supportive shoes for walking
• Drink plenty of fluids
• Eat a healthy, balanced diet

Safety Tips

• Don't over-do it. Stop exercising if you become short of breath and don't exercise to the point of exhaustion. If you feel short of oxygen, you may be compromising oxygen delivery to your developing baby.
• Don't take risks. Avoid any activity that could cause trauma to your abdomen.
• Don't perform exercises that involve bouncy, jerky motions. Avoid exercises that compress the uterus.
• During the second and third trimesters, don't do exercises that require you to lie flat on your back. This position is associated with a decrease in blood flow and oxygen delivery.

Warning Signs to Watch For

Stop exercising and call your doctor if you experience any of the following:

• Significant pain
• Vaginal bleeding
• Leaking fluid
• Feeling dizzy or faint
• Significant shortness of breath

When to Avoid Exercise

Avoid exercising if:

• You have risks for preterm labor
• You are bleeding or leaking fluid
• Your water has broken
• You have preeclampsia (high blood pressure from pregnancy)
• You have other medical conditions or complications that require limited activity
• You are on bedrest

Before exercising during pregnancy, talk with your health care provider about any limitations or precautions you should take.

Reviewed by health care specialists at UCSF Medical Center.

This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.