Finding out that you have gestational diabetes can be overwhelming. In addition to planning for the birth of your baby, expecting moms with gestational diabetes have to count carbohydrates, limit the amount of sugars they consume, and monitor their blood sugar. Gestational diabetes occurs in up to 10% of pregnancies and causes high blood sugar in women who did not have diabetes prior to pregnancy. [1,2] Without proper management, gestational diabetes can cause health problems in both you and your baby.  Your doctor will help you determine if your gestational diabetes can be managed through diet and lifestyle changes alone, or if you will need medications to help control your blood sugar. You can read more about gestational diabetes here.
Dietary modification is the preferred treatment option for expecting moms with gestational diabetes. If you have gestational diabetes, you should see a registered dietician to determine what meal plan is best for both you and your baby. Each expecting mom will require a slightly different meal plan depending on her pre-pregnancy weight and other factors. You will need to gain a certain amount of weight during pregnancy in order to provide enough nutrients to your growing baby. The amount of weight gain that is recommended by the American College of Obstetricians and Gynecologists depends on the mom’s pre-pregnancy height and weight.  Eating healthy and balanced meals ensures that you gain a healthy amount of weight during pregnancy and can reduce the likelihood that you will require medications to control your gestational diabetes.
Your dietician will determine how many calories you should consume each day and how those calories should be divided. The goal of a proper meal plan is to keep your blood sugar steady and prevent readings that are either too high or too low. Consuming an excessive amount of carbohydrates or sugars can cause your blood sugar to spike, whereas consuming an insufficient number of carbohydrates can cause the production of substances, called ketones, which can be harmful to you and your baby’s health.  Over time, ketones accumulate and cause your blood to become more acidic, which can lead to a life-threatening emergency. 
For expecting moms with gestational diabetes, it is recommended to consume a diet consisting of about 50% to 60% carbohydrates, 10% to 20% protein, and 25% to 30% fat.  These numbers may vary depending on your nutritional needs. It is also currently unclear which type of diet provides the best outcomes for moms and their babies. A recent study found that expecting moms with gestational diabetes who consumed a diet containing a higher percentage of total carbohydrates and a lower percentage of total fats had lower blood sugars overall.  However, many providers recommend consuming a diet that is lower in total carbohydrates and higher in total fats. Your dietician will choose which type of diet is best for you.
The types of carbohydrates that you consume are important for controlling your gestational diabetes. Expecting moms should ensure to consume healthy complex carbohydrates, such as whole grains, vegetables, peas, and beans, as opposed to refined carbohydrates. Refined carbohydrates have a high glycemic index and contain very few nutrients. The glycemic index gives an estimate of how much a carbohydrate-containing food will raise your blood sugar.  The higher the glycemic index of the food, the more it will raise your blood sugar. Therefore, it is best to consume foods with a medium or low glycemic index, or to consume a high glycemic index food with a low glycemic index food to balance it out. In addition, having fiber or fat with a carbohydrate-containing food usually lowers its glycemic index.
Although the glycemic index of a food describes the type of carbohydrate it contains, it does not tell you the amount of carbohydrates present. Since studies have shown that the amount of carbohydrates in food has a larger impact on blood sugar than the glycemic index, it is important to use carbohydrate counting to determine how many carbohydrates you should consume with each meal. For expecting moms with gestational diabetes, counting carbohydrates and consuming foods with a lower glycemic index can help you manage your blood sugar. Generally, foods with a lower glycemic index are also healthier and contain more vitamins and nutrients. Examples of low glycemic foods that are also nutritious include: sweet potatoes, peas, legumes, lentils, barley, oat bran, rolled or steel-cut oatmeal, most fruits, carrots, non-starchy vegetables, and 100% stone-ground whole wheat or pumpernickel bread. In contrast, white bread or bagels, puffed rice, corn flakes, russet potatoes, short grain white rice, pretzels, popcorn, and saltine crackers are high glycemic index foods with little nutritional value. Expecting moms should avoid processed foods and foods that are high in sugar because they can cause a spike in your blood sugar.
Soluble fiber is another ingredient that expecting moms should include in their diets. Both insoluble fiber and soluble fiber are healthy for your digestive health. Soluble fiber is especially beneficial in gestational diabetes because it slows the speed at which carbohydrates are digested, which can help prevent spikes in blood sugar after eating.  This type of fiber is found in many healthy low glycemic index foods, including peas, lentils, beans, oat bran, barley, and nuts.
The types of fat that you consume are also important when planning out your meals. Expecting moms should try to consume more monounsaturated fats or polyunsaturated fats and consume less saturated fats and trans fats.  Fats are high in calories, so they should be eaten in small portions depending on the amount of fat that your dietician recommends. Fish are high in omega-3 fatty acids and are also healthy sources of fat. However, expecting moms should avoid fish with a high mercury content.
If you have gestational diabetes, you also want to control how and when you eat your meals. It is usually recommended to eat 3 meals and 1 to 4 snacks per day. [7,12] You should try to eat your meals at around the same time each day. Additionally, the goal of meal planning is to keep your blood sugar stable. Consuming foods that contain soluble fiber or fat with carbohydrate-containing foods can prevent your blood sugar from quickly rising after a meal.  For example, a typical balanced breakfast may include fruit with either oatmeal and walnuts or toast and peanut butter. Expecting moms with gestational diabetes also need to continually monitor their blood sugar throughout the day. Your doctor will help you decide how often you should test yourself and how to manage low or high readings. Many expecting moms with gestational diabetes can control their blood sugar through diet and lifestyle changes alone. By incorporating some healthy dietary modifications into your routine, you can take control of your gestational diabetes and help keep your baby healthy.
- American Diabetes Association. What is Gestational Diabetes? Updated November 21, 2016. Accessed April 10, 2016.
- Centers for Disease Control and Prevention. Gestational Diabetes. Updated July 25, 2017. Accessed April 10, 2018.
- Serlin DC and Lash RW. Diagnosis and Management of Gestational Diabetes Mellitus. Am Fam Physician. 2009;80(1):57-62.
- The American College of Obstetricians and Gynecologists. Weight Gain During Pregnancy. 2016;548:1-3.
- WebMD. Meal Planning for Pregnant Women with Diabetes. Updated November 20, 2015. Accessed April 10, 2018.
- American Diabetes Association. DKA (Ketoacidosis) & Ketones. Updated March 18, 2015. Accessed April 10, 2018.
- Ashwal E and Hod M. Gestational diabetes mellitus: Where are we now? Clin Chim Acta. 2015 Dec 7;451(Pt A):14-20.
- Piper LK, Stewart Z, Murphy HR. Gestational diabetes. Obstetrics, Gynaecology and Reproductive Medicine. 2017;27(6):171-176.
- American Diabetes Association. Glycemic Index and Diabetes. Updated May 14, 2014. Accessed April 10, 2018.
- Food and Drug Administration. Dietary Fiber.
- American Diabetes Association. Fats. Updated August 13, 2015.
- U.S. National Library of Medicine. Diabetes diet – gestational. MedlinePlus. Updated April 5, 2018. Accessed April 10, 2018.