Gestational Diabetes

Gestational diabetes, or GDM, is a common condition that occurs during pregnancy, diagnosed roughly in the third trimester of pregnancy. As the name suggests, it is essentially similar to diabetes mellitus type 2 in that the patient has hyperglycemia (high blood sugar glucose ) and problems with insulin. These women do not have diabetes Mellitus from before, and it resolves after giving birth. In some women, there is a risk of getting diabetes mellitus type 2 after delivery that needs to be looked after. If left untreated, GDM can cause health problems for both mother and baby. The key is to seek medical attention early as it is manageable and not life-threatening if treated early.

Pregnancy exposes a woman’s body to tremendous changes both physically and hormonally. Several changes in the normal levels of hormones and physiological processes of the body occur to meet the challenges of pregnancy. Initially, in pregnancy, the glucose levels decrease, promoting fat deposition. Later, increased appetite causes increased glucose levels but a decrease in insulin sensitivity due to fats.

When the pregnant body is not able to produce enough insulin, accompanied by decreased insulin sensitivity, GDM develops. 

Gestational diabetes is classified into two types based on blood tests and the suggested management.

• Type A 1: In this type, there is an abnormal oral glucose tolerance test (OGTT) result, but normal blood glucose levels during fasting and 1-2 hours after meals. Diet modification is sufficient to control glucose levels.
• Type A 2: In this type, there is an abnormal OGTT compounded by abnormal glucose levels during fasting and or after meals. This type is managed by diet modification, therapy with insulin, or other medications.

Some of the factors that can increase your chances of having GDM are;

• Advanced maternal age
• Family history
• Polycystic ovarian syndrome (PCOS)
• Weight gain as an adult
• Having a poor diet
• Elevated BMI
• Women with heart disease
• Smoking
• Previous unexplained stillbirth 

In the U.S, annually, 2 – 10 % of pregnancies are affected by gestational diabetes (GDM). The risk increases with increased maternal age. It occurs in only 1% of women under 20, while 13% of women above 44 are affected by GDM.

Following are the signs and symptoms of GDM

• Polydipsia (increased thirst )
• Polyuria (increased urination)
• Fatigue
• Sugar in urine
• Nausea
• Blurred vision
• Infections of vagina, bladder, and skin with candida 

During pregnancy, a screening test for gestational diabetes is usually performed during the 24^th and 28^th weeks of pregnancy. If you have risk factors for GDM, you might be tested before the usual weeks.

• Glucose challenge test: You will be given a sugar syrup to drink, and the sugar levels will be checked. After one hour, blood sugar levels of more than 190mg/dl indicate gestational diabetes.
• Oral glucose tolerance test: You are made to fast for 12 hours, after which you are given the sugar solution to drink, and sugar levels are checked after 1, 2, and 3 hours. 

An increase in sugar levels during pregnancy can be due to;

• Type 1 diabetes which was undiagnosed before
• Type 2 diabetes
• MODY (mature onset diabetes of the young )

GDM goes away on its own once the mother delivers normally six days after delivery, so the treatment mainly revolves around a plan for management while pregnant. The management for the mother is a balanced diet, exercise, insulin if needed, and glucose monitoring.

• Eating meals on time, eating small portions, and being mindful of what one is eating are imperative. Avoiding junk /processed food and limiting the intake of sugary drinks, sweets, and desserts have proved beneficial in the treatment.
• Fruits and vegetables should be included in the diet along with protein and healthy fats.
• Along with dietary changes, the patient has to remain physically active. Physical activity 30 mins /day improves metabolic control, reduces insulin resistance, increases insulin production by the pancreas, reduces cardiovascular risk, improves weight control and overall wellbeing.
• Monitoring fetal activity and blood glucose before and after exercise.
• As pregnancy progresses,  glucose intolerance typically worsens; the patient may ultimately require insulin therapy.
• Medication is given if blood sugar levels are still not well controlled 1 to 2 weeks after changing diet and or exercising regularly or if blood sugar levels are very high.
• Most commonly used medications include; Glyburide and metformin orally.
• Insulin injections: Fast-acting insulin before a meal or intermediate or long-acting insulin that the patient takes at bedtime or upon waking.

Infant care: The management of an infant post-delivery is glucose infusion to help prevent the development of hypoglycemia. In GDM, the baby is usually delivered via c section because the baby is usually very large or is at health risk. The infant may develop neonatal jaundice (raised bilirubin), neonatal hypocalcemia (decreased calcium), hypoglycemia (decreased blood glucose ), breathing problems, obesity, premature birth, and type 2 diabetes. 

The treatment of GDM is important to prevent complications during delivery and afterward. A well-managed case has a good outcome. In most cases, GDM resolves after delivery. Some women with GDM are at risk of developing type 2 diabetes later. A blood test to check for the development of DM type 2 should be performed 6-13 weeks post-delivery and every 1-3 years later. Other complications include hypertension (high blood pressure ), insulin-related hypoglycemia, and recurrent GDM in 50 % of cases. If the second pregnancy occurs within a year of first, the chances of GDM recurrence are even higher.

One must consult their health care provider or diabetologist about daily diabetes management and ways to reduce the risk of diabetes before, during, and after pregnancy. Lifestyle changes can effectively manage 80-90%  of mild GDM cases.

Screening during pregnancy is important, so antenatal care with an obstetrician is fundamental, especially for mothers who are at risk. Blood sugar monitoring and medication are necessary in some cases. Lifestyle changes such as exercising regularly and dietary changes such as avoiding processed foods, sugary drinks, and a balanced amount of carbohydrates, proteins, fiber, and fat in the diet are crucial to prevent the later development of DM 2.

Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 19, 2023.

References

Gestational Diabetes | CDC

https://www.cdc.gov/diabetes/basics/gestational.html

Gestational Diabetes - Symptoms, Treatments | ADA

https://diabetes.org/diabetes/gestational-diabetes