Gestational Diabetes: Glucose Monitoring, Meal Planning, and Postpartum Screening

Who needs this teaching

Clients with gestational diabetes mellitus (GDM), usually diagnosed by screening at 24 to 28 weeks of gestation, and the person who shops and cooks. Placental hormones increase insulin resistance in the second and third trimesters. Maternal hyperglycemia causes fetal hyperinsulinemia, macrosomia, shoulder dystocia, and neonatal hypoglycemia, and increases the risk of preeclampsia and cesarean birth.

The priority teaching points

1. Blood glucose monitoring. Check capillary blood glucose 4 times daily: fasting on waking, and 1 or 2 hours after the start of each meal, as instructed. Usual targets are fasting below 95 mg/dL, 1-hour postprandial below 140 mg/dL, and 2-hour postprandial below 120 mg/dL, or the targets the provider sets. Record each result with the foods eaten. Bring the log or meter to every visit.
2. Medical nutrition therapy. Meet with a registered dietitian. Spread carbohydrates over 3 meals and 2 to 3 snacks, including a bedtime snack to prevent overnight ketosis. Choose high-fiber complex carbohydrates and pair them with protein. Eat a smaller carbohydrate portion at breakfast, because insulin resistance is highest in the morning. Avoid juice, regular soda, and sweets. Do not skip meals. Keep carbohydrate intake at a minimum of 175 g daily.
3. Activity. Walk for 10 to 15 minutes after each meal. Aim for at least 150 minutes of moderate activity weekly. Muscle contraction increases glucose uptake and lowers postprandial glucose.
4. Insulin when prescribed. When targets are not met with nutrition and activity, insulin is the preferred medication because it does not cross the placenta. Metformin and glyburide cross the placenta. Teach injection technique, site rotation, and storage. Insulin requirements rise as pregnancy advances.
5. Hypoglycemia. During insulin therapy, a blood glucose below 70 mg/dL is hypoglycemia. Signs are shakiness, diaphoresis, hunger, headache, and confusion. Treat with 15 g of fast-acting carbohydrate, such as 4 oz (120 mL) of juice or 4 glucose tablets. Recheck in 15 minutes and repeat until the glucose is 70 mg/dL or higher, then eat a snack or meal.
6. Fetal surveillance. From about 28 weeks, count fetal movements daily: 10 movements within 2 hours, or the method taught. Keep scheduled nonstress tests and growth ultrasounds. Report decreased movement to labor and delivery immediately.
7. After birth. Glucose usually returns to normal after birth. The newborn receives blood glucose checks. Complete a 75-g oral glucose tolerance test at 4 to 12 weeks postpartum. GDM indicates a lifelong increased risk of type 2 diabetes; screen every 1 to 3 years. Breastfeeding, a healthy weight, and regular activity lower this risk. Request early glucose screening in the next pregnancy.

Red flags the client reports

Teach-back questions

• "When will you check your blood sugar each day?"
• "What are your blood sugar targets?"
• "What will you eat for your bedtime snack?"
• "What will you do if your blood sugar is 65?"
• "Which test will you have after your baby is born, and when?"

Teaching tips

• Write the client's glucose targets and testing times on the handout.
• Observe a return demonstration of meter use and insulin injection.
• Schedule the postpartum glucose test before discharge.

Read more on NCLEXPace

• Insulin: Types, Timing, and the Questions Built On Them
• Chronic Disease Management: Hypertension, Diabetes, Hyperlipidaemia

Sources

• American College of Obstetricians and Gynecologists. Gestational Diabetes Mellitus: ACOG Practice Bulletin No. 190. Obstet Gynecol. 2018;131(2):e49-e64.