Gestational Diabetes Mellitus (GDM): Symptoms, Diagnosis and Treatment

Diabetes mellitus is a condition in which the blood sugar levels are abnormally high because the body is either not producing enough insulin or unable to use the insulin produced.

What is gestational diabetes mellitus (GDM)?

Gestational diabetes is a condition characterised by elevated blood sugar levels that arise specifically during pregnancy and typically resolve after childbirth. While it can occur at any point during pregnancy, gestational diabetes tends to be more prevalent in the second or third trimester.

What are the risk factors for developing gestational diabetes?

Risk factors for developing gestational diabetes in certain women may include the following: 

• Over 40 years old.
• Obesity.
• History of having a baby with a birth weight of 4.5kg or more.
• History of gestational diabetes during a previous pregnancy.
• Strong family history of diabetes.
• Polycystic Ovarian Syndrome (PCOS).
• Undergone gastric bypass or other weight-loss surgery.

What are the symptoms of gestational diabetes?

Gestational diabetes is typically asymptomatic. Most cases are discovered during screening for gestational diabetes.

However, some women may experience symptoms if their blood sugar levels are elevated (hyperglycaemia):

• Increased thirst.
• Frequent urination (more than usual).
• Dry mouth.
• Tiredness.
• Genital itching.

It is important to note that some of these symptoms can be common in pregnancy and may not necessarily indicate gestational diabetes. If you have concerns about any symptoms mentioned above, it is advisable to consult your doctor.

How does gestational diabetes affect pregnancy?

Most women with gestational diabetes experience otherwise normal pregnancies and give birth to healthy babies. However, there are some possible complications, such as:

• Larger than usual baby: Increases the likelihood of delivery by Caesarean section.
• Polyhydramnios: May cause premature labour.
• Premature birth: Delivering a baby before completing 37 weeks of pregnancy.
• Pre-eclampsia: A condition that causes high blood pressure during pregnancy and can cause complications if not addressed early.
• Baby may experience low blood sugar or develop jaundice (yellowing of the skin and eyes) after birth, which could necessitate medical treatment in a hospital.
• Stillbirth (a baby who dies before being born): A complication that has become increasingly rare in women with gestational diabetes due to effective blood sugar control and meticulous monitoring of both mothers and babies throughout pregnancy.

Mothers who have gestational diabetes also have an increased risk of developing type 2 diabetes later.

How is gestational diabetes diagnosed?

Testing for gestational diabetes is typically conducted between the 24th and 28th weeks of pregnancy. Nevertheless, if you have risk factors for gestational diabetes, testing may be initiated as early as your initial prenatal appointment.

Testing for gestational diabetes can be done in two ways:

Two-part test:

• On the day of the initial screening test, you can maintain your regular diet and fluid intake. You will be given a 50g glucose solution, often in the form of an orange or cola drink, which you should consume within a few minutes. 
• An hour later, your blood sugar level will be measured. If your blood sugar is within the normal range, no further tests are necessary. 
• Typically, your blood sugar level is considered high if it is above 130 to 140 mg/dL (7.2 to 7.7 mmol/L). A very high reading (≥200 mg/dL [11.1 mmol/L]) strongly indicates gestational diabetes. 
• If your initial screening result is high but not very high, you will need a follow-up test known as an oral glucose tolerance test (GTT). This involves measuring your fasting blood sugar level in the morning and then at one, two, and three hours after drinking a 100g glucose solution (twice the amount in the one-hour test), which is also usually in the form of an orange or cola drink. 
• It is important not to restrict your diet in the days leading up to the GTT, as limited food intake could lead to falsely elevated results. 
• Gestational diabetes is diagnosed if two or more blood sugar values during the GTT are elevated. However, some doctors may recommend treatment even after a single elevated result, especially if other signs of gestational diabetes are present, such as a larger-than-average foetus or excess amniotic fluid.

One-part test: 

• Some doctors use a different type of oral GTT. This test involves measuring your fasting blood sugar level in the morning and then at one and two hours after drinking a 75g glucose solution, typically in the form of a specially formulated orange or cola drink. 
• Gestational diabetes is diagnosed if one or more blood sugar values are elevated.

How is gestational diabetes treated?

If you are diagnosed with gestational diabetes, it is necessary to make diet adjustments, and you will need to monitor your blood sugar level. In certain instances, you might also need to learn how to administer insulin injections or take a pill to reduce your blood sugar levels.

1. Eating right

   The first treatment for gestational diabetes is eating right. The general guidelines below will help you until you receive your individualised food plan.

   • Continue with a healthy pregnancy diet: Maintain your commitment to a nutritious diet during pregnancy.
   • Frequent, balanced meals: Consume three small-sized meals and incorporate three to four healthy snacks into your daily eating routine. Aim to eat every two to three hours to evenly distribute your food intake throughout the day. Skipping meals is not advised, and paying attention to a bedtime snack can help regulate your fasting blood sugar levels.
   • Limit your sugar intake: Avoid sugary treats and pre-sweetened beverages. Use alternative sweeteners in moderation.
   • Incorporate protein with limited saturated fat: Include protein sources with low saturated fat content, such as lean cuts of red meat, pork, chicken, and fish. Be mindful of the types and amounts of fish you consume due to concerns about mercury. Additionally, other protein-rich foods like cheese, eggs, nuts, seeds, and peanut butter are also beneficial for both you and your baby.
   • Incorporate carbohydrates: Consume moderate portions of carbohydrates.
   • Limit fruit servings: Consume a small piece of fruit or approximately 1 cup at a time.
   • Include a variety of vegetables: Salads, greens (such as spinach, collards, and kale), broccoli, green beans, carrots, tomatoes, mushrooms, and other vegetables that you enjoy. 
   • Choose healthy fats: Olive oil or canola oil can be added in your cooking and meal preparation.

2. Blood sugar monitoring

   You should ideally check your blood sugar 4 times a day:

   • Before eating in the morning.
   • One or two hours after breakfast.
   • One or two hours after lunch.
   • One or two hours after dinner.

3. Exercise

   • While exercise is not a mandatory component of gestational diabetes treatment, it can be beneficial in managing blood sugar levels.
   • If you were already engaged in an exercise routine before being diagnosed with gestational diabetes, it is generally recommended to continue exercising.
   • If you did not have a regular exercise routine before, it is advisable to consult with your doctor or nurse to determine if exercise is suitable for you during pregnancy.
   • In most cases, women without medical or pregnancy-related complications can engage in at least moderate exercise throughout their pregnancy.

4. Insulin

   • Around 15% of women with gestational diabetes may need insulin. It is a medication that helps lower blood sugar levels, which in turn can help reduce the risk of complications associated with gestational diabetes.
   • Insulin is given by injection, and you may require one or two shots depending on your dose. 

5. Oral anti-hyperglycaemic medication

   • For women who are unwilling or unable to adhere to insulin therapy, oral anti-hyperglycaemic medication can be considered, provided they fully comprehend the limited information available regarding the long-term risks and benefits of these medications.

Make an appointment at Pantai Hospitals

Each pregnancy is unique. Regular prenatal appointments and open communication with your doctor are crucial for monitoring your health and addressing concerns throughout pregnancy.

A dedicated and expert team of Obstetricians and Gynaecologists at Pantai Hospital is available for consultation to provide patients with the best care and assistance. Get in touch with us to book an appointmenttoday if you have any questions about gestational diabetes in pregnancy. 

Pantai Hospital has been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.