Pregnancy Diabetes Management

What Is Gestational Diabetes?

Gestational Diabetes Mellitus (GDM) refers to glucose intolerance first occurring during pregnancy, typically diagnosed through glucose tolerance testing at 24-28 weeks of pregnancy. The occurrence of gestational diabetes is related to insulin resistance caused by hormonal changes during pregnancy. Under normal circumstances, the placenta secretes various hormones to maintain pregnancy, but these hormones work against insulin, increasing insulin resistance.

Diagnostic criteria for gestational diabetes are: fasting blood glucose ≥5.1 mmol/L, or 1-hour blood glucose ≥10.0 mmol/L, or 2-hour blood glucose ≥8.5 mmol/L. Meeting any of the above qualifies for diagnosis. The incidence of gestational diabetes varies by region and diagnostic criteria, with a global average incidence of approximately 1-14%, and can be as high as 20% or more in high-incidence areas.

Gestational diabetes poses potential risks to both the expectant mother and fetus. For the expectant mother, gestational diabetes increases risks of gestational hypertension, preterm birth, and cesarean section. For the fetus, gestational diabetes may cause macrosomia, neonatal hypoglycemia, respiratory distress syndrome, etc. Fortunately, these risks can be significantly reduced through good blood glucose management.

Pregnancy Blood Glucose Monitoring

Preconception Preparation and Early Screening

For women planning to become pregnant, especially those with diabetes risk factors, preconception consultation and assessment are very important. Risk factors include: previous gestational diabetes history, previous delivery of macrosomic infant, polycystic ovary syndrome, obesity (BMI≥30 or ≥25 for Asians), family history of diabetes, etc. Preconception fasting blood glucose and HbA1c testing should be performed to exclude pre-pregnancy diabetes.

Once pregnancy is confirmed, diabetes screening should be performed in early pregnancy. If fasting blood glucose ≥7.0 mmol/L or HbA1c ≥6.5% in early pregnancy, it may be pre-pregnancy diabetes rather than gestational diabetes, requiring closer monitoring and corresponding treatment. For most pregnant women, 75g oral glucose tolerance testing (OGTT) should be performed at 24-28 weeks of pregnancy to screen for gestational diabetes.

Starting folic acid supplementation before and in early pregnancy is an important measure for preventing fetal neural tube defects. For obese pregnant women, preconception weight loss of 5-10% can significantly reduce gestational diabetes risk. Gestational weight gain should also be controlled within a reasonable range—different pre-pregnancy BMI has different recommended gestational weight gain ranges.

Blood Glucose Management During Pregnancy

The goal of blood glucose management during pregnancy is to maintain blood glucose within normal ranges and reduce complication risks. Blood glucose control targets for gestational diabetes are stricter than for regular diabetes: fasting blood glucose should be controlled at 3.3-5.3 mmol/L, 1-hour postprandial blood glucose at 4.4-6.7 mmol/L, and 2-hour postprandial blood glucose at 4.4-6.7 mmol/L.

Dietary management is the foundation of gestational diabetes treatment. Small, frequent meals are recommended—3 main meals plus 2-3 snacks daily, avoiding consuming large amounts of carbohydrates at once. Carbohydrates should be low-glycemic-index foods such as whole grains, legumes, vegetables, etc. Protein and healthy fats should be balanced. Daily calorie intake should be individualized based on pre-pregnancy BMI and gestational weight gain.

Exercise is an important component of gestational diabetes management. Recommended exercise methods include walking, swimming, prenatal yoga, etc. Exercise should be performed 30-60 minutes after meals, lasting 20-30 minutes. If diet and exercise cannot achieve blood glucose targets, medication therapy needs to be initiated. Metformin and insulin are approved medication treatments for gestational diabetes.

Fetal Monitoring

Patients with gestational diabetes require a series of fetal monitoring to assess fetal intrauterine condition and detect abnormalities promptly.

Ultrasound examination is an important tool for fetal monitoring. Early pregnancy can confirm fetal heartbeat and intrauterine position. Fetal structural ultrasound examination in the second trimester can detect fetal malformations. After 28 weeks, regular ultrasound to assess fetal growth, amniotic fluid volume, and umbilical artery blood flow is recommended. Since gestational diabetes increases fetal malformation risk, fetal echocardiography is recommended.

Fetal heart monitoring is another important method for assessing fetal intrauterine condition. After 32 weeks, 1-2 weekly fetal heart monitoring is recommended. For patients with poor blood glucose control or other complications, more frequent monitoring may be needed. Fetal kick counting is also a simple method for pregnant women to self-monitor fetal condition—recording daily fetal movement counts after 28 weeks.

Timing and Method of Delivery

The timing of delivery for gestational diabetes patients needs comprehensive assessment based on blood glucose control, fetal condition, and other complications. For patients with good blood glucose control and no complications, delivery can be induced at 39-40 weeks. For patients with poor blood glucose control or complications, earlier delivery may be needed.

Regarding delivery method, gestational diabetes itself is not a cesarean section indication. However, gestational diabetes patients have increased risk of delivering macrosomic infants. When estimated fetal weight ≥4000g, elective cesarean section can be considered. Vaginal delivery is possible, but blood glucose and fetal condition should be closely monitored during labor.

Blood glucose should be maintained at 4-7 mmol/L during labor. It is usually recommended to stop oral glucose-lowering drugs during labor and switch to insulin intravenous infusion. Newborn blood glucose should be monitored immediately after delivery to promptly detect and handle neonatal hypoglycemia.

Frequently Asked Questions

Q1: Will gestational diabetes resolve after delivery?

Most gestational diabetes patients return to normal blood glucose after delivery. However, gestational diabetes patients have increased risk of recurrence in subsequent pregnancies—approximately 30-50% will develop gestational diabetes in subsequent pregnancies. At the same time, gestational diabetes patients have increased future risk of type 2 diabetes—it is recommended to perform glucose tolerance testing at 6-12 weeks postpartum to assess.

Q2: Can gestational diabetes patients have vaginal delivery?

Gestational diabetes itself is not a contraindication for vaginal delivery. If blood glucose is well controlled, fetal estimated weight is appropriate, and there are no other complications, trial of vaginal delivery can be attempted. However, close monitoring of blood glucose and fetal condition during labor is required.

Q3: How should gestational diabetes patients breastfeed?

Breastfeeding is beneficial for gestational diabetes patients—it can help lower blood glucose and weight. However, nutritional intake during breastfeeding needs attention to ensure sufficient calories and fluids. If using insulin, dosage may need adjustment. It is recommended to breastfeed under professional guidance.

This content is for reference only and cannot replace professional medical advice. For health concerns, please consult your doctor.