Is it safe to exercise while pregnant?

Most moms-to-be know that exercising during pregnancy can be a big plus for mood and physical health. But how much is too much? We asked Justin Thompson, MD, an avid cyclist and physician at Women’s Health in Palo Alto, about what advice he gives to his patients.

As an Obstetrician and avid cyclist, I am very passionate about the numerous benefits of physical activity for my patients before, during, and after pregnancy. In the past, it was common for physicians to tell their pregnant patients to go on bed rest during pregnancy. But for the majority of healthy women with low-risk pregnancies, bed rest is no longer advised — and can actually be harmful. Bed rest during pregnancy increases a woman’s risk of blood clots and also decreases muscle mass and aerobic capacity, which can make childbirth and caring for a newborn challenging.

The safety and benefits of exercise during pregnancy have been demonstrated in many studies. Exercise is associated with a lower incidence of gestational diabetes, hypertensive disorders of pregnancy, cesarean delivery, and excessive gestational weight gain. Exercises that have been studied and appear to be safe in pregnancy include: walking, swimming, stationary cycling, elliptical, low-impact aerobics, yoga, running or jogging, racquet sports, and strength training. Exercises to avoid include: contact sports (ice hockey, boxing, soccer, basketball), activities with a high risk of falling (downhill skiing, water skiing, surfing, roller blading, mountain biking, gymnastics, and horseback riding) as well as scuba diving, sky diving, and hot yoga.

Before continuing a current program or starting a new workout regimen, pregnant women should first check with their obstetrician. There are several conditions in pregnancy that can make exercise dangerous, including: significant heart disease, lung disease, incompetent cervix or cerclage, multiple gestation at risk of premature labor, persistent bleeding in the 2nd or 3rd trimester, placenta previa after 26 weeks, premature labor during the current pregnancy, ruptured membranes, preeclampsia or pregnancy-induced hypertension, and severe anemia.

A good goal is to exercise throughout pregnancy for 30 minutes at least five times a week at moderate intensity, which means being able to carry on a conversation during exercise. Pregnancy is not the best time to take on a new sport such as riding a bike or training for your first marathon. For pregnant patients who have a high level of skill and comfort with certain activities, such as outdoor cycling, it may be safe to continue those activities throughout the majority of the pregnancy after a conversation with their doctor.

I also remind my patients to stop exercising and check with their obstetrician if they experience warning signs, such as regular painful contractions, bleeding or amniotic fluid leakage, shortness of breath at rest, dizziness, headache, chest pain, calf pain or swelling or muscle weakness affecting balance.

In addition to the numerous physical benefits of exercise during pregnancy, the mental health benefits of exercise during this stressful time in a woman’s life should not be overlooked. I integrate my background as an athlete into my practice to help my patients achieve their health and fitness goals throughout pregnancy, including helping my patients find safe ways to continue their pre-pregnancy physical activities and return to their normal routine as soon as possible following the birth of their baby.

Dr. Thompson is one of three physicians currently accepting patients at Women’s Health in Palo Alto, a small group practice focused on providing the best Obstetric and Gynecologic care to women throughout the Peninsula.