The American College of Obstetricians and Gynecologists recommends at least 150 minutes per week of moderate-intensity aerobic activity for healthy pregnant women. New research suggests that water exercise can be a beneficial part of a prenatal exercise plan.

Since pregnancy causes many changes in the body, including shifts in the mother’s center of gravity and the way muscles and joints feel, activities may need to be modified. Women who have difficulty performing land exercises can still gain the physiological benefits from water exercise.

A review published by Spanish journal Metas de Enfermería in 2014 affirmed moderate aquatic exercise as a safe and effective exercise option during pregnancy. It cited increased maternal interest in exercise in aquatic settings as reason for the review.

Excessive weight gain during pregnancy is linked with complications like hypertension and gestational diabetes. A recent study in the American Journal of Health Promotion found evidence that regular aquatic fitness can help mothers maintain a healthy pregnancy weight without affecting birth weight. It analyzed 111 pregnant women with who had no pregnancy complications. One group received three weekly sessions of aerobic and resistance aquatic activities from weeks 10 to 12 until weeks 38 to 39, while the other was the control group. The aquatic activities group showed a lower percentage of excessive maternal weight gain with no change in birth weight.

A study in Medicine and Science in Sports and Exercise examined if exercise can reduce gestational diabetes risks, using a combination of land and water activities. Findings showed a reduction in gestational diabetes in those adhering to both land and water exercise, which included aerobic activity and muscular conditioning.

But water exercise isn’t appropriate for all moms to be. For example, a woman with a high-risk pregnancy may have activity restrictions. Facilities also should note that water temperature and ventilation play a role in safety for pregnant women. Pools with thermoneutral temperatures above 93 to 94 degrees can cause overheating during exercise. Improperly ventilated natatoriums also can cause harm to the fetus if the mother inhales disinfection byproducts.

Special thanks to the National Swimming Pool Foundation.

Studies Referenced:
Bacchi, M., Mottola, M. F., Perales, M., Refoyo, I., & Barakat, R. (2017). Aquatic Activities During Pregnancy Prevent Excessive Maternal Weight Gain and Preserve Birth Weight. American Journal of Health Promotion, Epub ahead of print.

Cordero, Y., Mottola, M. F., Vargas, J., Blanco, M., & Barakat, R. (2015). Exercise is associated with a reduction in gestational diabetes mellitus. Medicine and Science in Sports and Exercise, 47(7), 1328–1333. Retrieved from

Iglesias Constante, S. M. (2014). Review of the efficacy of aquatic exercise during pregnancy. Metas de Enfermería. Retrieved from