Researchers at Norwegian University of Science and Technology, in Trondheim, assessed whether exercise during pregnancy might prevent gestational diabetes and improves insulin resistance.

First, the details.

  • 855 women in gestational week 18 to 22 were randomly assigned to a treatment group for 12 weeks.
    • Standard exercise program, which followed standard recommendations and included moderate-intensity to high-intensity activity 3 or more days per week
    • Standard antenatal care

And, the results.

  • At 32 to 36 weeks of gestation:
    • No differences between groups in prevalence of gestational diabetes
    • No differences in insulin resistance between groups after adjusting for values before the study
  • Outcomes of pregnancy were similar between groups.
  • Only 55% of women in the exercise group managed to follow the recommended exercise protocol.
  • No serious adverse events related to physical exercise were seen.

The bottom line?

The authors concluded, “There was no evidence that offering women a 12-week standard exercise program during the second half of pregnancy prevents gestational diabetes or improves insulin resistance in healthy pregnant women with normal body mass indexes.”

The results should not be interpreted to recommend against exercise. WebMD tells us, “Maintaining a regular exercise routine throughout your pregnancy can help you stay healthy and feel your best. Regular exercise during pregnancy can improve your posture and decrease some common discomforts such as backaches and fatigue. There is evidence that physical activity may… relieve stress, and build more stamina needed for labor and delivery.”

Both WebMD and Mayo Clinic also recommend exercise during pregnancy to reduce the risk of gestational diabetes. Although these latest findings may cause a reassessment of this recommendation.

According to Mayo Clinic, “For most pregnant women, at least 30 minutes of moderate exercise is recommended on most, if not all, days of the week — but even shorter or less frequent workouts can help you stay in shape and prepare for labor.”

2/16/12 22:51 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.