Gestational Diabetes: Symptoms, Diet, and Management

Does gestational diabetes cause symptoms?

Most people with gestational diabetes have no noticeable symptoms — which is why routine screening between 24 and 28 weeks of pregnancy is standard practice 1Ref 1American Diabetes Association Professional Practice Committee (2024).15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes — 2024.Screening, blood sugar targets, dietary approach, insulin use, postpartum testing, and long-term type 2 diabetes risk in gestational diabetes2Ref 2American College of Obstetricians and Gynecologists (2018).ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus.Two-step 50-gram/100-gram screening approach; screening timing at 24–28 weeks; insulin as preferred pharmacologic treatment; postpartum 6–12 week glucose test recommendation. When symptoms do occur they can include increased thirst, frequent urination, and fatigue, but these are also common in normal pregnancy, which is why screening rather than symptom awareness is the primary detection method.

The diagnosis is made through glucose tolerance testing: the two-step approach uses a 50-gram one-hour screening test followed, if elevated, by a 100-gram three-hour diagnostic test. A single two-hour 75-gram test is used in some settings 2Ref 2American College of Obstetricians and Gynecologists (2018).ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus.Two-step 50-gram/100-gram screening approach; screening timing at 24–28 weeks; insulin as preferred pharmacologic treatment; postpartum 6–12 week glucose test recommendation.

Why does blood sugar matter during pregnancy?

The placenta produces hormones that naturally create some insulin resistance in pregnancy — a mechanism that ensures the baby receives glucose. In some pregnancies the pancreas cannot compensate adequately, and blood sugar rises. Elevated glucose crosses the placenta, causing the baby's pancreas to produce extra insulin. The main concerns with poorly controlled gestational diabetes include 1Ref 1American Diabetes Association Professional Practice Committee (2024).15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes — 2024.Screening, blood sugar targets, dietary approach, insulin use, postpartum testing, and long-term type 2 diabetes risk in gestational diabetes2Ref 2American College of Obstetricians and Gynecologists (2018).ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus.Two-step 50-gram/100-gram screening approach; screening timing at 24–28 weeks; insulin as preferred pharmacologic treatment; postpartum 6–12 week glucose test recommendation:

• Macrosomia (large baby). Excess glucose fuels rapid fetal growth, increasing the risk of delivery complications including shoulder dystocia.
• Neonatal hypoglycemia. After birth, the baby no longer receives glucose from the mother but may continue producing excess insulin, causing low blood sugar.
• Preterm birth and cesarean delivery. Both are modestly more likely.
• Preeclampsia. High blood pressure in pregnancy is more common with gestational diabetes.
• Future diabetes risk. People who develop gestational diabetes have a meaningfully elevated lifetime risk of developing type 2 diabetes; postpartum screening and ongoing lifestyle attention address this.

What does the gestational diabetes diet look like?

Dietary management is the foundation of gestational diabetes treatment. The goal is to maintain blood sugar within target ranges throughout the day without restricting nutrients the baby needs. Key principles:

Carbohydrate distribution, not elimination. Carbohydrates raise blood sugar, but they are a necessary fuel for mother and baby. The approach is to spread carbohydrate intake across three moderate meals and two to three snacks rather than consuming large amounts at once. A registered dietitian experienced in gestational diabetes can help set personalized carbohydrate targets.

Breakfast is the most sensitive meal. Many people find that blood sugar is most difficult to control after the morning meal because cortisol (naturally elevated in the morning) increases insulin resistance. Lower-carbohydrate breakfast options — eggs, protein, non-starchy vegetables, small amounts of whole grain — often produce better glucose readings than cereal or juice.

Food quality matters. Choosing complex carbohydrates (oats, legumes, whole grains, vegetables) over refined ones (white bread, sugary drinks, pastries) slows glucose absorption and produces gentler blood sugar rises. Pairing carbohydrates with protein or fat at each meal has the same effect.

Foods that are often well tolerated: eggs, Greek yogurt (plain), nuts, cheese, lean proteins, non-starchy vegetables (leafy greens, broccoli, zucchini), berries in moderate portions, lentils and beans.

Foods that commonly spike blood sugar: fruit juice, white rice, white bread, sweetened yogurt, breakfast cereal, pastries, sugary beverages — even natural ones like smoothies with large amounts of fruit.

How is blood sugar monitored at home?

A glucometer (fingerstick blood glucose meter) is used to check glucose at defined times, typically: - Fasting — first thing in the morning before eating - One or two hours after the start of meals

Your obstetric team will give you specific target ranges; typical targets are around 95 mg/dL or less fasting and around 120–140 mg/dL or less at one or two hours after meals, though these vary by provider and guideline 1Ref 1American Diabetes Association Professional Practice Committee (2024).15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes — 2024.Screening, blood sugar targets, dietary approach, insulin use, postpartum testing, and long-term type 2 diabetes risk in gestational diabetes. Keeping a log of readings helps the care team adjust the plan.

Continuous glucose monitors (CGMs) are increasingly used in gestational diabetes and can provide a more complete picture of glucose trends, though access and coverage vary.

When is medication needed?

Diet and monitoring alone control gestational diabetes successfully in the majority of cases. When blood sugar targets are not met consistently despite dietary adherence, insulin is typically added 2Ref 2American College of Obstetricians and Gynecologists (2018).ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus.Two-step 50-gram/100-gram screening approach; screening timing at 24–28 weeks; insulin as preferred pharmacologic treatment; postpartum 6–12 week glucose test recommendation. Insulin is safe in pregnancy — it does not cross the placenta — and effectively lowers glucose.

Oral medications (metformin, glyburide) are used in some settings, though insulin remains the most studied and widely recommended pharmacologic option during pregnancy. The decision is made by the obstetric team based on glucose patterns.

What happens after delivery?

Gestational diabetes typically resolves after the placenta is delivered. A glucose test at six to twelve weeks postpartum confirms that blood sugar has returned to normal 2Ref 2American College of Obstetricians and Gynecologists (2018).ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus.Two-step 50-gram/100-gram screening approach; screening timing at 24–28 weeks; insulin as preferred pharmacologic treatment; postpartum 6–12 week glucose test recommendation. It is important not to skip this test, because gestational diabetes is a significant risk factor for type 2 diabetes. Ongoing healthy eating, regular physical activity, and periodic glucose checks in subsequent years reduce that long-term risk 1Ref 1American Diabetes Association Professional Practice Committee (2024).15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes — 2024.Screening, blood sugar targets, dietary approach, insulin use, postpartum testing, and long-term type 2 diabetes risk in gestational diabetes.