How safe is exercise during pregnancy?

Two lines on a home pregnancy test, a flickering heartbeat on ultrasound, and suddenly your world has changed: you’re pregnant! Regardless of where this new path takes you, you may start to examine your daily decisions in a new way as you discover an intense drive to protect the growing baby inside you. Even your exercise routines may come under scrutiny, particularly if late-night Googling has you second-guessing everything that you believed you knew.

Just how safe is exercise during pregnancy?

The short answer? Exercise during pregnancy is not only safe, it’s encouraged. An overriding principle for pregnancy is: what is good for mom is good for baby. The American College of Obstetricians and Gynecologists (ACOG) and the US Office of Disease Prevention and Health Promotion note that exercising during pregnancy may reduce

• weight gain
• risk for gestational diabetes, particularly in overweight or obese women
• risk for cesarean delivery.

Plus, it helps pregnant women prevent or manage inevitable aches and pains. Regular physical activity during pregnancy may help psychological well-being and possibly even reduce depression and anxiety during the postpartum period. Additionally, women who exercise during pregnancy may recover more quickly after the birth.

How active should you be?

Best-laid plans aside, the ACOG recommends engaging in moderate activity for 20 to 30 minutes on three to seven days per week throughout your pregnancy. It is safest to avoid exercising for longer than 45 minutes in one session to prevent hypoglycemia (low blood sugar).

The best time to boost your activity level is before you conceive. Generally, you can safely continue to exercise at the level of strenuous activity you practiced before your pregnancy. So, if you enjoyed moderate activity, stick with that rather than ramping up during your pregnancy. If you enjoyed vigorous activity, you may be able to continue this, though it’s safest to check with your obstetric team to be sure.

Of course, many women become pregnant without an established exercise routine in place. If this is true for you, start slowly and ramp up gradually. For example, try walking a few more times per week, then add to the amount of time you walk. Finally, you might step up intensity by walking more quickly.

What types of exercise can you do?

The best exercises to engage in are activities you actually enjoy doing. Pregnant women can generally do brisk walking, swimming, stationary cycling, low-impact aerobics, yoga or Pilates, and running. Most of these activities can be modified for your growing belly.

There are some activities you should avoid, including:

• contact sports that could cause injury, such as basketball, hockey, or soccer
• sports that are risky or likely to cause falls, such as skiing, surfing, or gymnastics
• scuba diving
• hot yoga or hot Pilates, because increases in body temperature might harm a fetus.

What if you have a high-risk pregnancy?

What if your pregnancy is not straightforward? High-risk pregnancies come in a variety of forms. Often, they occur when women have complex medical conditions (such as epilepsy or lupus), develop a condition that could affect the pregnancy (such as a short cervix or placenta previa), or if the fetus has a complex condition (such as a heart defect).

Usually, doctors recommend mild activity like walking or stretching, because it isn’t linked to poor outcomes, such as inadequate growth or preterm delivery. Even if you have a high-risk condition where vigorous activity is discouraged, you and your doctor can come up with an individualized plan for light, safe activities.

Although bed rest was advised in the past for certain high-risk conditions, it hasn’t been shown to improve outcomes. And unfortunately, bed rest can put you at a higher risk for blood clots, loss of bone density, and deconditioned muscles, which could further complicate your pregnancy. The mood-boosting benefits of exercise may be even more critical in high-risk pregnancies.

The bottom line

Whether you are new to exercise or a lifelong athlete, physical activity is generally safe and well tolerated in pregnancy. With rare exceptions, mild to moderate exercise offers physical and psychological benefits. If you have a high-risk pregnancy, your obstetrician can help you choose activities that will be safe for you and your baby. Pregnancy is the first step along the journey of parenthood. Let regular physical activity now become part of a lifetime of dedication to good health for your family.