Gestational Diabetes: Risks & Management

Gestational diabetes is a type of diabetes that develops during pregnancy. It's characterised by high blood sugar levels in women who didn't have diabetes before pregnancy. Managing gestational diabetes is crucial for a healthy pregnancy and delivery in Chennai.

What Is Gestational Diabetes?

Gestational diabetes mellitus (GDM) is defined as glucose intolerance that is first recognised during pregnancy. Pregnancy hormones can interfere with insulin, leading to insulin resistance. In my clinical experience, many women are surprised to learn they have gestational diabetes, as it often presents with no obvious symptoms. The good news is that with proper management, most women can have healthy pregnancies and babies.

The condition typically develops during the second or third trimester, usually between 24 and 28 weeks of gestation, and generally disappears after delivery. However, having gestational diabetes increases the risk of developing type 2 diabetes later in life. According to a recent meta-analysis, factors such as high BMI, family history of diabetes, non-white ethnicity, and advanced maternal age are associated with an increased risk of developing type 2 diabetes after gestational diabetes. It's important to note that GDM is consistently associated with adverse pregnancy, maternal and foetal outcomes, regardless of the diagnostic criteria used.

The diagnosis is made through blood tests, primarily the oral glucose tolerance test (OGTT). This test involves drinking a sugary solution and then having your blood sugar levels checked at regular intervals over a two-hour period. Current NICE guidelines recommend diagnosing GDM in women with a fasting glucose level of 5.6 mmol/L or higher, or a two-hour plasma glucose level of 7.8 mmol/L or higher during the OGTT. ICMR recommends testing for GDM twice during antenatal care. The first testing should be done during first antenatal contact as early as possible in pregnancy. The second testing should be done during 24-28 weeks of pregnancy if the first test is negative.

Causes and Risk Factors of Gestational Diabetes

The exact cause of gestational diabetes isn't fully understood, but several factors contribute to its development. Pregnancy hormones can block the action of insulin, leading to insulin resistance. The pancreas then has to work harder to produce enough insulin to keep blood sugar levels stable. When the pancreas can't keep up, gestational diabetes develops.

Several risk factors increase the likelihood of developing gestational diabetes:

• Obesity or Overweight: Women with a body mass index (BMI) of 30 or higher are at a higher risk.
• Family History: Having a family history of diabetes, especially in a first-degree relative (parent, sibling), increases the risk.
• Previous Gestational Diabetes: Women who had gestational diabetes in a previous pregnancy are more likely to develop it again.
• Age: Women over the age of 25 are at a higher risk.
• Polycystic Ovary Syndrome (PCOS): PCOS is associated with insulin resistance, increasing the risk of gestational diabetes.
• Ethnicity: Certain ethnic groups, including South Asians, have a higher prevalence of diabetes and gestational diabetes.
• Previous Delivery of a Large Baby: Having previously delivered a baby weighing 4.5 kg or more.

Patients often ask me how they can reduce their risk. While some risk factors are unavoidable, maintaining a healthy weight before pregnancy, eating a balanced diet, and engaging in regular physical activity can help lower the risk. If you have risk factors, it's essential to discuss them with your doctor during your first antenatal visit.

Signs and Symptoms of Gestational Diabetes

One of the challenges with gestational diabetes is that it often presents with no noticeable symptoms. Many women only discover they have the condition during routine screening tests. However, some women may experience mild symptoms that can easily be mistaken for normal pregnancy discomforts:

• Increased Thirst: Feeling unusually thirsty, even after drinking plenty of fluids.
• Frequent Urination: Needing to urinate more often than usual.
• Fatigue: Feeling more tired than usual, even with adequate rest.
• Blurred Vision: Experiencing temporary blurred vision.
• Increased Appetite: Feeling hungrier than usual, despite eating regularly.

It's crucial to remember that these symptoms can also be attributed to normal pregnancy changes. Therefore, routine screening is essential for early detection. According to the American Diabetes Association (ADA), all pregnant women should be screened for gestational diabetes between 24 and 28 weeks of gestation. If you have risk factors, your doctor may recommend earlier screening. If you experience any of these symptoms, especially if you have risk factors, it's important to discuss them with your doctor. Early detection and management can significantly reduce the risk of complications.

How Gestational Diabetes Is Diagnosed

Diagnosing gestational diabetes involves a two-step process: a screening test followed by a diagnostic test if the screening results are elevated.

1. Glucose Screening Test (GCT): This test is typically performed between 24 and 28 weeks of gestation. You will drink a sugary solution (usually 50 grams of glucose), and your blood sugar level will be measured one hour later. A blood sugar level of 140 mg/dL (7.8 mmol/L) or higher is considered elevated and requires further testing. Some clinics may use a lower threshold of 130 mg/dL (7.2 mmol/L).

2. Oral Glucose Tolerance Test (OGTT): If the screening test is positive, you will need to undergo a three-hour OGTT. This test requires fasting for at least eight hours before the test. You will then drink a more concentrated glucose solution (usually 75 or 100 grams), and your blood sugar levels will be measured at one, two, and three hours after drinking the solution.

The diagnostic criteria for gestational diabetes vary slightly depending on the guidelines used. Based on the Carpenter-Coustan criteria, gestational diabetes is diagnosed if two or more of the following values are met or exceeded:

Based on the National Diabetes Data Group (NDDG) criteria, gestational diabetes is diagnosed if two or more of the following values are met or exceeded:

A diagnosis of GDM is made if one or more values are met or exceeded according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria:

• Fasting: ≥ 92 mg/dL (5.1 mmol/L)
• 1 hour: ≥ 180 mg/dL (10.0 mmol/L)
• 2 hour: ≥ 153 mg/dL (8.5 mmol/L)

It's important to follow your doctor's instructions carefully before and during the OGTT to ensure accurate results.

Treatment Options for Gestational Diabetes in Chennai

The primary goal of gestational diabetes treatment is to maintain blood sugar levels within a healthy range to protect both the mother and the baby. Treatment typically involves a combination of lifestyle modifications and, in some cases, medication.

1. Dietary Changes: A healthy diet is the cornerstone of gestational diabetes management. This typically involves:

   • Balanced Meals: Eating regular, balanced meals with a focus on whole grains, lean proteins, vegetables, and healthy fats.
   • Carbohydrate Control: Limiting simple carbohydrates and sugary foods and drinks. The ADA recommends limiting carbohydrate intake to 35% to 45% of the total daily energy intake.
   • Smaller, Frequent Meals: Eating smaller meals more frequently throughout the day to help stabilise blood sugar levels.
   • Professional Guidance: Consulting a registered dietitian or nutritionist to develop a personalized meal plan.

2. Regular Exercise: Physical activity helps improve insulin sensitivity and lower blood sugar levels. Aim for at least 30 minutes of moderate-intensity exercise, such as walking, most days of the week. Always consult your doctor before starting any new exercise program during pregnancy.

3. Blood Glucose Monitoring: Regular self-monitoring of blood glucose levels is essential. This involves checking your blood sugar several times a day using a glucose meter. Your doctor will provide specific instructions on when and how often to check your blood sugar. Target fasting plasma glucose <95 mg/dL (5.3 mmol/L) and either 1-hour postprandial glucose <140 mg/dL (7.8 mmol/L) or 2-hour postprandial glucose <120mg/dL (6.7 mmol/L).

4. Medication: If lifestyle modifications are not enough to control blood sugar levels, your doctor may prescribe medication.

   • Insulin: Insulin is often the first-line medication for gestational diabetes. It is safe for both the mother and the baby.
   • Metformin: Metformin is an oral medication that can help improve insulin sensitivity. However, it is not always recommended during pregnancy, and its use should be discussed with your doctor. Network meta-analyses suggest that metformin had the highest probability of being the most effective treatment in reducing the risk of most outcomes compared with insulin.

Treatment plans are individualised based on the patient's needs and blood sugar response.

Lifestyle Changes and Prevention

While you can't completely eliminate the risk of gestational diabetes, several lifestyle changes can help reduce your risk and manage the condition effectively.

• Maintain a Healthy Weight: If you are planning to become pregnant, try to achieve and maintain a healthy weight before conception.
• Eat a Balanced Diet: Focus on a diet rich in fruits, vegetables, whole grains, and lean proteins. Limit sugary drinks, processed foods, and saturated fats.
• Stay Active: Engage in regular physical activity, such as walking, swimming, or prenatal yoga.
• Manage Stress: Practice stress-reducing techniques such as meditation, deep breathing exercises, or spending time in nature.
• Get Enough Sleep: Aim for 7-8 hours of quality sleep each night.
• Monitor Blood Sugar Levels: If you have risk factors for gestational diabetes, monitor your blood sugar levels regularly, even before pregnancy.

Remember, even with these lifestyle changes, some women may still develop gestational diabetes. The key is to detect it early and manage it effectively to ensure a healthy pregnancy.

When to See a Fertility Specialist

While gestational diabetes is typically managed by an obstetrician or endocrinologist, consulting a fertility specialist like myself, Dr. Rukkayal Fathima, may be beneficial in certain situations. If you have a history of infertility, PCOS, recurrent miscarriages, or other fertility-related issues, seeking guidance from a fertility specialist can provide comprehensive care. I practice across multiple locations in Chennai, including Mylapore and Chetpet, and have experience assisting over 3000 couples.

A fertility specialist can help:

• Optimize your overall health and fertility: Before, during, and after pregnancy.
• Manage underlying conditions: That may contribute to both infertility and gestational diabetes.
• Provide personalized treatment plans: Tailored to your specific needs and medical history.
• Offer advanced reproductive technologies: If needed, to help you conceive and maintain a healthy pregnancy.

For personalised guidance, book a consultation with Dr. Rukkayal Fathima.