Gestational Diabetes

The prevalence of GDM in India varied from 3.8 to 21% in different parts of the country, depending on the geographical locations and diagnostic methods used. GDM has been found to be more prevalent in urban areas than in rural areas.

What is Gestational diabetes?

Pregnant women who have never had diabetes before but who have high blood glucose (sugar) levels during pregnancy are said to have gestational diabetes. According to a 2014 analysis by the Centers for Disease Control and Prevention, the prevalence of gestational diabetes is as high as 9.2%.

It is Important to monitor because it impacts maternal health care both during/after pregnancy and increases perinatal complications. Gestational diabetes affects the mother in late pregnancy, after the baby’s body has been formed, but while the baby is growing. Because of this, gestational diabetes does not cause the kinds of birth defects sometimes seen in babies whose mothers had diabetes before pregnancy.

Who is at risk?

Gestational Diabetes Generally women who are 25 years of age, Overweight or obese state, with Family history of diabetes mellitus, History of abnormal GTT, History of poor obstetric outcome, History of delivery of an infant with a birth weight > 9 lbs , History of polycystic ovary syndrome, Asian origin.

Screening tests and Diagnosis of Gestational diabetes mellitus

In the antenatal clinic, a pregnant woman after undergoing preliminary clinical examination, has to be given a 75 g oral glucose, without regard to the time of the last meal. A venous blood sample is collected at 2 hours for estimating plasma glucose.

GDM is diagnosed if 2 hr plasma glucose is ≥140 mg/dl. American Diabetes Association recommends 3 hour 100 gm OGTT and Gestational Diabetes Mellitus is diagnosed if any 2 values meet or exceed FPG > 95 mg/dl, 1 hr PPG > 180 mg/dl, 2 hr PG > 155 mg/dl and 3 hr PG > 140 mg/dl.

Screening is recommended between 24 and 28 weeks of gestation and the diagnostic criteria of ADA are applicable.

Treatment and Management of Gestational diabetes

A team approach is ideal for managing women with GDM. The team would usually comprise an obstetrician, diabetes physician, a diabetes educator, dietitian, midwife and pediatrician. Intensive monitoring, diet and insulin is the corner stone of GDM management. A short term intensive care gives a long term pay off in the primary prevention of obesity, IGT and diabetes in the offspring, as the preventive medicine starts before birth.

Primary requisite is the need for glucose monitoring. Diet control should be initiated. If still poor control persists, insulin should be commenced. The most advised format is Self-monitoring of blood glucose (SMBG).

Target

Maintaining a mean plasma glucose (MPG) level ~105–110 mg/dL is desirable for a good fetal outcome.

This is possible if FPG and 2-hour postprandial peaks are ~90 mg/dL and ~120 mg/dL respectively.

Medical Nutrition Therapy

All women with GDM should receive nutritional counseling. The meal pattern should provide adequate calories and nutrients to meet the needs of pregnancy. The expected weight gain during pregnancy is 300–400 g per week and total weight gain is 10–12 kg by term.

Initiating Insulin Therapy

Once diagnosis is made, medical nutritional therapy (MNT) is advised initially for 2 weeks. If MNT fails to achieve control, i.e. FPG ~90 mg/dL and/or post-meal glucose ~120 mg/dL, insulin may be initiated.

Monitoring Glycemic Control
The success of the treatment for a woman with GDM depends on the glycemic control maintained with meal plan or pharmacological intervention.

Self-monitoring of blood glucose self-monitoring of blood glucose (SMBG) on a daily basis, failing which, at least weekly monitoring should be encouraged.

Follow- up of Gestational Diabetes Mellitus

Gestational diabetic women require follow-up. An OGTT with 75 g oral glucose, using WHO criteria for the non-pregnant population should be performed at 6–8 weeks postpartum. If found normal, glucose tolerance test is repeated after 6 months and every year to determine whether the glucose tolerance has returned to normal or progressed. A considerable proportion of gestational diabetic women may continue to have glucose intolerance. It is important that women with GDM be counseled with regard to their increased risk of developing permanent diabetes.

Complications that may affect the baby include:

  • Larger body than normal – difficult for delivery and harmful for the baby
  • Sometimes jaundice – seen as yellowing of skin and white of eyes
  • Hypoglycaemia or very low blood sugar right after birth
  • Breathing problems
  • Higher chances of death
  • Increased risk of becoming overweight and developing type II diabetes in future

In addition to the above risks in babies, women with gestational diabetes will be at risk for:

  • Developing gestational diabetes in the subsequent pregnancies
  • Type II diabetes in later stages of life
  • Having high blood pressure and too much protein in the urine, a condition called preeclampsia
  • Having caesarean surgery to deliver the baby because the baby may be large
  • Becoming depressed

Therefore, along with the usual healthcare delivered by the obstetrician or gynaecologist, pregnant women with gestational diabetes will require other healthcare professionals including a diabetologist, dietician, diabetes educator to effectively manage their health and well-being.

If a woman already has type I or type II diabetes, it is essential to discuss with the doctor before becoming pregnant, as poorly controlled blood sugar levels can seriously impact the baby’s health.

Prevention of Gestational Diabetes Mellitus

There are no guarantees in preventing Gestational diabetes mellitus but adopting healthy habits before pregnancy is always a better option. A few healthy choices like eating healthy food- high on fiber and low in fat, focusing on vegetables, fruits and whole grains and most importantly exercising before and after pregnancy can be of major help. Focusing on permanent changes in eating habits, motivating yourself by remembering the long-term benefits of losing weight help in reducing the risk of having diabetes in the future or developing type 2 diabetes down the road.

FAQs

1. Is my baby at risk now I have gestational diabetes?

Gestational diabetes affects the mother in late pregnancy, after the baby’s body has been formed, but while the baby is growing. Because of this, gestational diabetes mellitus does not cause the kinds of birth defects sometimes seen in babies whose mothers had diabetes before pregnancy. So the baby might not be at risk most of the times. But there might be higher chances of the baby becoming obese in future. Exercise and healthy diet are always the best prevention methods.

2. Will I still have diabetes after the baby is born?

Some new mothers have better blood glucose control in the first few weeks after delivery. For many, it’s a period of odd blood glucose swings. If you have gestational diabetes, there is a very good chance that your diabetes will go away immediately after the delivery. If the condition still persists, it is always advised to consult your doctor and continue medication.

3. Will I have to be induced now that I have gestational diabetes?

However, women can technically be treated as ‘normal’ if their gestational diabetes is well controlled and baby’s growth looks normal on a 32 week scan. Many OB’s cite the risk of stillbirth as a reason for induction, because the risk of stillbirth in women with regular diabetes is higher.

However, there is no evidence that the risk of stillbirth goes up in gestational diabetes. So it is not necessary that having gestational diabetes mellitus needs induction od delivery.

4. Will I need a Caesarean section now that I have gestational diabetes?

A caesarean section might be required if it is suspected that the baby is 4,500 grams or higher, according to the American congress of Obstetricians and Gynecologists. In other cases f the glucose is under control, c-section is not required.

5. What should I expect at my first diabetes clinic appointment?

In the antenatal clinic, a pregnant woman after undergoing preliminary clinical examination, has to be given a 75 g oral glucose, without regard to the time of the last meal. A venous blood sample is collected at 2 hours for estimating plasma glucose.

GDM is diagnosed if 2 hr plasma glucose is ≥140 mg/dl. American Diabetes Association recommends 3 hour 100 gm OGTT and Gestational Diabetes Mellitus is diagnosed if any 2 values meet or exceed FPG > 95 mg/dl, 1 hr PPG > 180 mg/dl, 2 hr PG > 155 mg/dl and 3 hr PG > 140 mg/dl.

A care team at the clinic usually comprising an obstetrician, diabetes physician, a diabetes educator, dietitian, midwife and pediatrician. Intensive monitoring, diet and insulin is the corner stone of GDM management. A short term intensive care gives a long term pay off in the primary prevention of obesity, IGT and diabetes in the offspring, as the preventive medicine starts before birth.

6. What can/can’t I eat?

All women with GDM should receive nutritional counseling. The meal pattern should provide adequate calories and nutrients to meet the needs of pregnancy. The expected weight gain during pregnancy is 300–400 g per week and total weight gain is 10–12 kg by term.

7. Will I need to take medication or insulin to control my gestational diabetes?

Once diagnosis is made, medical nutritional therapy (MNT) is advised initially for 2 weeks. If MNT fails to achieve control, i.e. FPG ~90 mg/dL and/or post-meal glucose ~120 mg/dL, insulin may be initiated. The success of the treatment for a woman with GDM depends on the glycemic control maintained with meal plan or pharmacological intervention.

Self-monitoring of blood glucose self-monitoring of blood glucose (SMBG) on a daily basis, failing which, at least weekly monitoring should be encouraged.

8. Can a pregnant woman get diabetes?

Pregnant women who have never had diabetes before but who have high blood glucose (sugar) levels during pregnancy are said to have gestational diabetes. It is Important to monitor because it impacts maternal health care both during/after pregnancy and increases perinatal complications.

9. At what point will my diabetes consultant want to put me on medication or insulin?

Once diagnosis is made, medical nutritional therapy (MNT) is advised initially for 2 weeks. If MNT fails to achieve control, i.e. FPG ~90 mg/dL and/or post-meal glucose ~120 mg/dL, insulin may be initiated.

10. What tests are used to diagnose gestational diabetes?

Gestational diabetes mellitus is diagnosed if 2 hr plasma glucose is ≥140 mg/dl. American Diabetes Association recommends 3 hour 100 gm OGTT and Gestational Diabetes Mellitus is diagnosed if any 2 values meet or exceed FPG > 95 mg/dl, 1 hr PPG > 180 mg/dl, 2 hr PG > 155 mg/dl and 3 hr PG > 140 mg/dl.

Glycosylated hemoglobin, or hemoglobin A1c, is another test that may be performed. This test is used to monitor long-term blood glucose levels in people with diabetes. The hemoglobin A1c level offers a measure of the average blood glucose level over the past few months.

11. Signs of gestational diabetes mellitus?

Gestational diabetes typically does not cause any noticeable signs or symptoms. This is why screening tests are so important. Rarely, an increased thirst or increased urinary frequency may be noticed.

12. Diet of gestational diabetes mellitus?

It is not necessary to go on a special diet when have gestational diabetes. Depending on your current diet, you may have to eat less of some foods and more of others. The main aim for managing gestational diabetes is ensuring that your blood glucose levels are under control, so your healthcare team will discuss targets that are right for you.

All carbohydrates will have an impact on your blood glucose levels so be aware of how much you eat. Try to choose nutritious carbohydrate-containing foods such as wholegrain starchy foods, pulses, fruit and vegetables as well as some dairy foods. Your healthcare team will help you understand how carbohydrates affect your blood glucose levels. You may be advised to:

  • eat less carbohydrate
  • choose better sources of carbohydrates
  • spread your carbohydrates throughout the day

Ask to be referred to a dietitian who can support you to come up with a specific eating plan that is tailored to your needs.

13. Gestational diabetes effects on baby?

Gestational diabetes may also have some effects on the baby’s health. High insulin levels in the baby (caused by high blood glucose levels in the mother) may lead to low blood glucose levels in the baby after birth, so the baby is more likely to need to be cared for in a specialist baby unit in the hospital. Because your baby may be larger than normal, he or she is at higher risk for these complications. Remember, these are just possible complications. Your baby might have none of them.

14. What are ketones and how can I prevent them?

Ketones are the result of the body burning fat for energy or fuel. For a person with diabetes, ketones are often the result of prolonged high blood sugar and insulin deficiency. Stringent control on blood sugars is the key in controlling ketones in the body. The presence of ketones can quickly become a dangerous condition called diabetic ketoacidosis, which is a serious medical emergency, and requires prompt treatment.

15. Does Metformin have any effects on the baby?

There are no known side effects to the baby from taking Metformin in pregnancy. However, studies are going on to check the long-term side effects on babies born from mothers who took metformin during pregnancy.

16. Gestational diabetes symptoms

Gestational diabetes typically does not cause any noticeable signs or symptoms. This is why screening tests are so important. Rarely, an increased thirst or increased urinary frequency may be noticed.

17. Gestational diabetes treatment

Treatment for gestational diabetes aims to keep blood glucose levels equal to those of pregnant women who don’t have gestational diabetes. Treatment for gestational diabetes always includes special meal plans and scheduled physical activity. It may also include daily blood glucose testing and insulin injections. Maintaining a mean plasma glucose (MPG) level ~105–110 mg/dL is desirable for a good fetal outcome. This is possible if FPG and 2-hour postprandial peaks are ~90 mg/dL and ~120 mg/dL respectively.

18. I feel sick and shaky and I’m sweating, what is wrong with me?

What you probably experienced were symptoms of low blood sugar called as hypoglycaemia. This happens when the blood sugar falls below 72mg/dl. It is very important for you to realise the symptoms and take immediate action. The symptoms of hypoglycaemia initially are sweating, tremor, hunger, anxiety, shakiness, headache, confusion, irritability, lack of concentration and if left untreated, hypoglycemia can get worse and may cause confusion, clumsiness, fainting, fits or even coma.

Ideally, when possible, low blood sugar should be confirmed by measuring the blood glucose level.

19. If I have another baby will I get gestational diabetes again?

There are many factors that affect how likely you are to develop gestational diabetes. While some of these, such as your ethnic origins, are out of your control, there are others that you can do something about. Making positive changes now will only benefit you and your next baby. Aim to be a healthy weight before you get pregnant. Try to bring your BMI (body mass index) below 25. Try not to put on weight between pregnancies. If you knew your BMI before your last baby, try not to add more than three BMI points to your pre-baby score. Putting on weight may mean you’re more likely to develop gestational diabetes again. It may also increase your risk of developing type 2 diabetes in later life.

Regular exercise, healthy diet are the two key concepts in keeping gestational diabetes mellitus at bay.

What are the causes of gestational diabetes?

Gestational diabetes is a condition of impaired blood sugar regulation in pregnancy, showing high levels of glucose or sugar in blood. Normally when a person eats food, the body digests the food to glucose and other nutrients which enter bloodstream. Glucose is an essential nutrient used as a fuel by every cell for all the normal processes. But for glucose to be utilized it should enter the every cell, and this can occur only in the presence of a hormone called insulin, produced by the pancreas. Without insulin, glucose a fuel that provides energy to for the body cells cannot enter the cells and gets retained in the blood.

Gestational diabetes happens when the amount of insulin released by mother’s body cannot be sufficient for maintaining sugar control. During pregnancy, a supporting tissue called placenta gets formed which connects the mothers and baby’s blood supply. It mainly provides nutrition to the baby; in addition to that, it also produces various hormones useful for baby’s growth and development. These hormones block the action of insulin in the mother’s body, a state termed as insulin resistance, which requires mother’s body to produce more amount of insulin, i.e., up to 3 fold than normal for maintaining sugar control. Even then, the blood sugars cannot be brought to normal resulting in gestational diabetes.

Sometimes, mother’s body can have insulin resistance even before the pregnancy usually because of being overweight, and these women start pregnancy with an increased need of insulin, and are more likely to develop gestational diabetes.

One can have higher chances of developing gestational diabetes if positive for:

  • Age above 25 years
  • Being overweight (BMI above 30)
  • Have had gestational diabetes before
  • Have given birth to a baby weighing more than 9 pounds
  • Have a parent, brother, or sister with type 2 diabetes
  • Have prediabetes, meaning your blood glucose levels are higher than normal yet not high enough for a diagnosis of diabetes
  • Are African American, American Indian, Asian American, Hispanic/Latina, or Pacific Islander American
  • Have a hormonal disorder called polycystic ovary syndrome, also known as PCOS

Sign & symptoms of gestational diabetes?

Usually, gestational diabetes may not cause any noticeable diabetes sign or symptoms. It is therefore crucial for every pregnant woman to get checked for sugar levels during their 8-12 weeks of pregnancy. If the result shows a high risk of gestational diabetes, a full-check-up of sugar testing will be required during the 24-28 weeks of pregnancy.

Sometimes, due to the high blood sugar levels, they may experience with symptoms like:

  • Blurred vision
  • Fatigue
  • Frequent infections – bladder, vagina, and skin
  • Increased thirst and urination
  • Nausea and vomiting
  • Weight loss although have increased appetite

Women with gestational diabetes should not ignore their health checks even if they do not show any symptoms, as this form diabetes does not cause any sign or symptoms.

Apart from the regular health checks, as a part of monitoring of gestational diabetes, the health care team may advise the women to test for

  • Blood pressure – a sharp rise can occur at 20th week of pregnancy, a condition called ‘preeclampsia’ and swollen face and hands are associated symptoms
    • can be fatal and result in long term problems if ignored
  • The presence of ketones – indicates that the fat from the mother’s body is broken down to ketones which are harmful for the baby.

Sometimes, the doctor may also advise some tests helpful to examine the baby’s health such as:

  • Ultrasound exams, which use sound waves to make images that show your baby’s growth and whether your baby is larger than normal
  • A non-stress test, which uses a monitor placed on your abdomen to check whether your baby’s heart rate increases as it should when your baby is active
  • Kick counts to check the time between your baby’s movements

How can gestational diabetes be treated?

The treatment of gestational diabetes must be strictly followed as persistent sugar levels in pregnancy can harm both the mother and the baby. Management always includes special diet regimens, physical activity and may also require insulin injections and glucose monitoring. If gestational diabetes is confirmed, the treatment should be immediate as persistently high sugar levels in pregnancy can harm both the mother and foetus.

Managing Gestational Diabetes:

  • Appropriate dietary changes that may include:
    • A balanced diet with more fruits and vegetables
    • Restricting fat intake to 30% or less than the daily calories
    • Eating food rich in unsaturated fats such as
      • Nuts and seeds
      • Soybean, corn, sunflower oil
      • Fatty fish such as salmon, mackerel, herring and trout.
  • Follow the dietary plan prescribed by the dietician. It’s important to write down everything one eats to keep track of weight. Appropriate dietary changes that may include:
  • More frequent monitoring of blood glucose (advised by the diabetes expert along with individual targets of blood glucose) This will include doing a home blood sugar test one or more times a day. If you know that your blood sugar level is within target, you will be at ease.
  • Increased physical activity
  • Moderate exercise for at least 150 minutes per week, particularly aerobic exercise – brisk walking, swimming, dancing, or low-impact aerobics
  • Avoid activities which may hit your stomach or risk a fall
  • In the third trimester, one should avoid exercise on the back as blood flow to the baby may be restricted.
  • Controlling weight gain during pregnancy helps prevent type 2 diabetes in future
  • Sometimes Medication
    • If blood sugar cannot be controlled over first one to two weeks with lifestyle changes, doctor can advise you medication, mainly insulin injections or oral anti-diabetics if necessary.
  • Monitoring foetal well-being

Monitoring foetal movements, or kick counts, helps a doctor find out if the foetus is moving less than usual. Foetal ultrasounds reveal how well the baby is growing and a non-stress test shows how well the baby’s heart responds to movement.

As per the physician’s suggestion, the woman may require to regular check the sugar levels and Indian guidelines recommend the below targets:

Target for women with gestational diabetes (to be confirmed after discussion with your physician)

TIME POINT OF BLOOD SUGAR TESTING SUGAR LEVEL
Before meals and when you wake up Around 90 mg/dL
2 hours after eating Around 120 mg/dL