Section 1: Metabolism / Glucose Regulation (Pregnancy, GDM, IDM, Weight Gain)

Metabolic changes in early pregnancy

Glucose needs increase for fetal growth; maternal insulin does not cross placenta, so fetus makes own insulin; increased glucose use may cause maternal hypoglycemia.

Metabolic changes in late pregnancy

Insulin resistance develops due to placental hormones (especially human placental lactogen), ensuring more glucose available for fetus.

Why does insulin resistance occur in late pregnancy?

Because of production of human placental lactogen (hPL) which increases maternal insulin resistance.

When is GDM screening performed?

Between 24-28 weeks of gestation.

Describe the Glucose Challenge Test (GCT)

Non-fasting test with 50g oral glucola; blood drawn in 1 hour; normal <140 mg/dL.

What happens if the 1-hour GCT is >140 mg/dL?

A 3-hour fasting Glucose Tolerance Test (GTT) is performed.

Diagnostic criteria for GDM (3-hour GTT)

Fasting >95 mg/dL, 1 hr >180 mg/dL, 2 hr >155 mg/dL, 3 hr >140 mg/dL; 2 or more elevated values = diagnosis.

How is gestational diabetes managed?

Diet control, blood glucose monitoring (fasting and 2-hour postprandial), exercise, and possibly medication (glyburide or insulin).

Target fasting and 2-hour postprandial glucose for GDM

Fasting <95 mg/dL; 2-hour postprandial <120 mg/dL.

Percentage of GDM patients managed with diet alone

Approximately 80-85%.

Oral medication used for GDM management

Glyburide.

When is insulin therapy indicated in GDM?

If diet and exercise fail to maintain glucose control (about 15% of women).

Key nursing education for GDM

Teach blood glucose monitoring, dietary management, exercise, and importance of fetal surveillance.

Definition of IDM

Infant of a diabetic mother.

Priority nursing care for IDM

Initiate early feedings, monitor glucose hourly, prevent cold stress, and give dextrose infusion if needed.

Complications seen in IDM

Macrosomia, birth trauma, respiratory distress, hypoglycemia, hyperbilirubinemia, polycythemia, cardiomyopathy, and stillbirth.

Why does hypoglycemia occur in IDM?

Infant continues to produce high insulin after birth but loses maternal glucose supply.

Appropriate total weight gain during pregnancy for normal BMI

25-35 pounds.

Weight gain pattern for normal BMI

1st trimester: 2-5 lbs; 2nd & 3rd trimesters: about 1 lb per week.

Weight gain for underweight woman

Total 28-40 lbs; about 1.5 lbs per week in 2nd & 3rd trimesters.

Weight gain for overweight woman

Total 15-25 lbs; about 0.5 lbs per week in 2nd & 3rd trimesters.

Weight gain for obese woman

Total about 11-20 lbs; about 0.4 lbs per week in 2nd & 3rd trimesters.

Extra daily calories needed during pregnancy

About 340-450 additional calories per day.

Total additional calories needed across pregnancy

Approximately 68,000-80,000 calories.

Meaning of "eating for two" in pregnancy

Only requires a small caloric increase (340-450 extra calories daily), not double the intake.