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What Is Gestational Diabetes During Pregnancy?

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Marissa is the writer of ThePracticalMommy and the blog Mommy Knows What's Best. She is a stay-at-home mom to four and was a teacher.

Everything You Need to Know About Gestational Diabetes

Everything You Need to Know About Gestational Diabetes

Gestational Diabetes in Pregnancy

More and more, pregnant women in the United States are facing an ailment that can have negative consequences for both mothers and babies: gestational diabetes.

Diabetes is a condition wherein the body cannot regulate its sugar levels, resulting in high or low blood sugar levels. Why is this becoming more prevalent with pregnant women? According to studies, more women are entering pregnancy as obese. Obesity is a high-risk factor for diabetes. Some of these women have diabetes pre-pregnancy while others develop it after their pregnancy hormones take over.

On the other side, there are just as many fit and healthy pregnant women who find out they have gestational diabetes. Why is that the case?

What is this form of diabetes during pregnancy? Here you will read about the condition gestational diabetes, how it is caused, and how it can be both prevented and treated.

What Is Gestational Diabetes?

Gestational diabetes occurs when a pregnant woman's body cannot control her blood sugar effectively, causing her to have high blood sugar. 6% to 9% of all pregnant women develop gestational diabetes.

The pancreas is responsible for emitting the sugar-controlling substance insulin into the blood to help remove excess amounts of sugar from the body. Sometimes, the pancreas produces too much insulin, and other times it doesn't produce enough. When it doesn't produce enough insulin, it cannot help remove sugar, causing high blood sugar.

During pregnancy, hormonal increases change the levels of insulin produced by the pancreas, making it so that the pancreas cannot keep up with the production of insulin needed to regulate blood sugar. If this continues, gestational diabetes is what occurs. Most of the time, this happens to pregnant women between the 24th and 28th week, although it can occur earlier in the pregnancy.

Signs of Gestational Diabetes

While most women may never have any signs of gestational diabetes, some have reported extreme thirst, extreme fatigue, nausea, frequent urination, and blurred vision. It's easy to see why some women don't realize something is wrong as these signs are common during pregnancy!

Others report changes they notice, like frequent bladder infections or feeling different after eating certain foods.

Symptoms of Gestational Diabetes

These are some of the common symptoms for gestational diabetes.

extreme thirst

frequent urination

too much amniotic fluid

extreme fatigue

nausea and vomiting

blurred vision

glucose intolerance

Complications of Gestational Diabetes

Complications for the Baby

Uncontrolled diabetes before pregnancy and/or untreated gestational diabetes early in the pregnancy can both have negative consequences for your baby.

  • Developmental Defects. Complications such as heart or brain defects can occur in the first trimester, while in the second and third trimester your baby may be considered to have macrosomia (being bigger than the average baby) and may have to increase insulin production on its own to help with your excess sugar problem.
  • Increased Size. If the baby is bigger at birth, it may have difficulties during the laboring process, resulting in damaged nerves and muscles in the shoulders if delivered vaginally. Some of these babies may not be able to pass through the birth canal due to their size, resulting in a c-section.
  • Insulin Imbalance and Jaundice. Once delivered, some babies may experience a drop in blood sugar since their insulin production was high while in the womb but no longer needed once they are delivered. Others may experience a condition called jaundice where the baby's body can not break down a substance called bilirubin, which is produced when red cells in the body are broken down. (Jaundice is common for newborns, although it is more prevalent for babies of gestational diabetics.)
  • Risk of Obesity and/or Diabetes. Later in life, the baby may experience a problem with obesity and can develop a form of diabetes.

Complications for the Mother

Aside from having to deal with the symptoms of gestational diabetes, there are other complications a pregnant woman might face if her diabetes is not under control.

  • Preeclampsia is a major complication that a pregnant woman might face. Also called pregnancy-induced hypertension, it is a condition characterized by excess amounts of protein in your urine and high blood pressure. It usually occurs after the 20th week of pregnancy. If not treated, it can be the cause of your baby not getting enough nutrients plus it can lead to eclampsia, which is seizures along with high blood pressure.
  • Macrosomia. Another complication would be the macrosomia mentioned above, which means you have a chance of having a baby that is over 8 pounds or more. While babies that big can be delivered vaginally, you may be at a higher risk of having a c-section. Your doctor should monitor your baby's growth, especially in the latter part of pregnancy.
  • Risk of Developing Type 2 Diabetes. After the pregnancy, you'll be at a higher risk of developing Type 2 diabetes. It can be avoided if you get back down to a healthy weight by eating a healthy diet and exercising regularly.
A baby may need to be treated after birth for jaundice, a condition that may be caused by gestational diabetes.

A baby may need to be treated after birth for jaundice, a condition that may be caused by gestational diabetes.

Symptoms of Preeclampsia

  • High Blood Pressure
  • Fluid Retention
  • Results from Urine or Blood Tests
  • Abdominal Pain
  • Nausea
  • Vomiting
  • Fever
  • Blood in Urine
  • Loss of Vision
  • Drowsiness

How to Avoid Gestational Diabetes

You can avoid gestational diabetes by achieving your ideal weight before pregnancy, eating a healthy diet, and exercising regularly. You can, however, still get gestational diabetes even if you do those things.

There's no way of knowing prior to pregnancy how your body will react to the pregnancy hormones that inhibit proper insulin production. If you show no signs of it or have no risk factors, you won't be tested for it until you are between 24 and 28 weeks along.

Risk Factors for Gestational Diabetes

During your prenatal visits with your doctor or midwife, your medical history will be examined. If you have any of the following risk factors for gestational diabetes, you may be tested earlier in your pregnancy than normal:

  • Being overweight or obese
  • Belonging to a high-risk ethnic group, such as African-American, American Indian, Asian American, Hispanic, or Pacific Islander
  • Having excess sugar in urine
  • Unable to properly process glucose
  • Having a family history of diabetes
  • Giving birth to a 9-pound baby previously
  • Having gestational diabetes in a previous pregnancy
  • Having too much amniotic fluid

You may have a few of these risks or you may have none of them. If you show no signs of gestational diabetes early in pregnancy, you won't be tested for it until later in the pregnancy.

As was mentioned, if you have a high risk for gestational diabetes, you may be tested early in the pregnancy so treatment can be given right away. If not, you'll be tested between 24 and 28 weeks, when gestational diabetes is most likely to be present.

Blood Tests for Gestational Diabetes

Blood will be drawn for both the glucose challenge test and the glucose tolerance test to determine gestational diabetes.

Blood will be drawn for both the glucose challenge test and the glucose tolerance test to determine gestational diabetes.

Pregnancy Glucose Test

The tests used to determine gestational diabetes are called a pregnancy glucose tolerance tests. They are blood tests using an oral glucose solution. There are two types used during pregnancy: a glucose challenge test (GCT) and a glucose tolerance test (GTT).

If you are at high risk for gestational diabetes, you will be given the glucose challenge test at the beginning of your pregnancy. This is the same test they will administer to all expectant mothers (even those who are not high risk) between 24-28 weeks. This is a non-fasting, one-hour test that involves drinking an oral glucose solution that has 50 grams of glucose and drawing blood after an hour to see how your body responds to the glucose.

How to interpret this test:

If the results are negative, you do not have gestational diabetes. If your test results are positive, your doctor will order a glucose tolerance test.

Glucose Tolerance Test

The glucose tolerance test is a three-hour fasting blood test. For three days before the test, you will be asked to consume more carbohydrates than what you're used to, which usually amounts to something like a piece of bread with every meal. Twelve hours before you go for the bloodwork, you'll need to fast or stop eating and drinking (although you can drink water).

When you go in for the test, your blood will be drawn to get your fasting blood sugar numbers. Then you will be given an oral glucose solution with 100 grams of glucose to drink. Every hour for three hours your blood will be drawn to see how your body is reacting to the glucose solution.

How to interpret this test:

Each blood draw and your blood sugar level at each draw will be examined. If all are negative, you are not at risk for gestational diabetes. If one or more of the results is positive, you probably have gestational diabetes.

3-Hour Gestational Diabetes Test

  • Fasting, for 12 hours
  • Blood drawn before glucose solution is given for your fasting blood sugar numbers
  • Oral glucose solution with 100 grams of glucose is given
  • Blood is drawn every hour for three hours

What is the 3-Hour test like?

I had this test done in early pregnancy. It is not fun, especially if you are prone to morning sickness. I developed a severe headache and nausea, mostly during the last two hours of the test. It is a necessary evil, though.

Glucose Levels for Gestational Diabetes

For the one-hour glucose challenge test, your blood sugar levels should remain below 130-140 milligrams of glucose per deciliter of blood plasma (mg/dL). If it is more than that (most doctors will consider anything above 140 mg/dL to be high), then you will need the 3-hour glucose tolerance test.

Fasting glucose levels vs. 3-hour levels

There are four different readings from your glucose tolerance test: the fasting levels, and the three-hour levels. For the fasting level, your blood sugar should remain below 95 mg/dL. For the first hour, your blood sugar levels should be below 180 mg/dL. For the second hour, your blood sugar levels should be below 155 mg/dL. For the third hour, your blood sugar levels should be below 144 mg/dL.

How to interpret the numbers:

Again, if your numbers are high for any two or more of those numbers, you will be considered a gestational diabetic. If your numbers are high for only one, you may not be considered diabetic but your pregnancy will still be closely monitored.

Results of a Glucose Tolerance Test

After my glucose tolerance test, I was told that my fasting level was at 95 mg/dL, which is considered by my doctor to be a high normal level. My other three levels were fine, but he asked me to see a dietitian for an 1800 calorie ADA diet. I'll also have extra ultrasounds towards the end of my pregnancy to monitor the size of the baby.

Since only one of my levels was elevated, I am not considered a gestational diabetic.

If you have gestational diabetes, you may need to use insulin injections.

If you have gestational diabetes, you may need to use insulin injections.

Treatment of Gestational Diabetes

Pregnant women with gestational diabetes will need to be on a special diet and monitor their glucose levels at home using a glucose meter or glucose testing strips. They will also need to get about 30 minutes of exercise a day as exercise is known to help regulate blood sugar.

If diet and exercise do not help with the blood glucose levels, then insulin supplements may be needed, either in the form of an oral supplement or insulin injections.

Those who are on the boarderline--not diabetic but close--will need to adhere to a special diet and get regular exercise.

All who show signs of gestational diabetes and those who have it will need special monitoring of their babies. Extra ultrasounds will be ordered to measure the baby's size.

What to Eat When You Have Gestational Diabetes

The special diet needed for gestational diabetes is akin to a regular diabetic diet: low carbohydrates, less fat and sugar, and more protein. Usually, meals are broken down into three meals a day with three snacks in between. One or more carbohydrates and one protein must be eaten at every meal, while snacks are mostly carbs like fruit, starches, or milk.

The recommended diet for me (I'm right at the border, but not diabetic) is the 1800 calorie American Diabetic Association (ADA) diet. According to my dietitian, I wouldn't be watching calories as much as watching carbs, the amount of fiber in foods, and my portions. My total carbs for the day need to be at least 175 grams per day, no more, no less, and my portions need to be the recommended sizes you'd see in My Plate.

Along with watching portions and keeping track of carbs, I also need to avoid sugary drinks and foods. That can be a hard thing for a pregnant woman (craving chocolate, anyone?), but I was told that a little sugary snack here and there, as long as it was counted with everything else I ate, wouldn't be such a bad thing.

Your doctor may suggest a different meal plan based on your condition and other factors that are particular to you and your pregnancy. Whatever is suggested is best to follow to ensure a healthy pregnancy for you and your baby.

My Plate Guidelines

Meal Plan for Gestational Diabetes

Example meal plan for gestational diabetes using the 1800 calorie ADA diet.

BreakfastSnack 1LunchSnack 2DinnerSnack 3

1 egg

1 small apple

Chef's salad

1 whole wheat English muffin

Chicken fajitas

1/2 corn muffin

2 slices whole wheat toast with butter

1 oz cheese

5 whole grain crackers

1 oz cheese

Mushrooms, onions, and peppers

cream cheese

Sliced ham


1 glass milk


1 oz cheese

1 small yogurt

Coffee with non-calorie sweetener

1 1/4 cups watermelon

2 small whole wheat tortillas

Gestational Diabetes After Pregnancy

The good news for gestational diabetics is that the diabetes should go away after the birth of the baby. Testing for glucose levels might need to be done at or about the six-week check-up.

To avoid developing Type 2 diabetes in the future, it is recommended that you try to get yourself to a healthy weight with a balanced diet and exercise. It may take you a while to get back to your pre-pregnancy weight, but as long as you try to be healthy you'll minimize your chances of developing diabetes later in life.

Have a happy and healthy pregnancy!


  1. What to Expect When You're Expecting- My favorite pregnancy book and an awesome resource for pregnancy issues.
  2. Baby Center - Excellent site for all things pregnancy and babies.
  3. Every Day Health - This site has great information about everything there is to know about gestational diabetes during pregnancy.

Pregnancy with Gestational Diabetes

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2012 Marissa


Marissa (author) from United States on September 17, 2012:

Just Ask Susan, thank you for sharing your story. Having gestational diabetes the first time around would have made me eat better as well with the other pregnancies, but I didn't come close until my third one. It does make you think about everything you put into your body, for both you and the baby.

Thanks for reading and commenting! :)

Susan Zutautas from Ontario, Canada on September 16, 2012:

I had gestational diabetes for my first pregnancy, which was twins. I never had any symptoms or problems. I was told that I probably had it due to carrying twins. I followed the diet to a T, and tested my blood several times a day. Everything turned out fine. With my second pregnancy (single child) I was fine but because of the gestational diabetes the first time around I did watch what I ate.

Excellent hub that I'm sure will be so helpful for those that experience this.

Marissa (author) from United States on September 15, 2012:

teaches12345, thankfully, with the help of doctors and families, pregnant women can go on to have happy and healthy pregnancies! Thanks for reading and commenting! :)

Marissa (author) from United States on September 15, 2012:

randomcreative, thank you very much! I have done a lot of research on this topic since I am dealing with it now. :)

Dianna Mendez on September 14, 2012:

Very well done! A friend just recently had a baby and she dealt with this during the entire pregnancy. She did fine with the help of her doctor and family. Great hub post and it will help many out there who are pregnant.

Rose Clearfield from Milwaukee, Wisconsin on September 14, 2012:

What a comprehensive overview!

Marissa (author) from United States on September 14, 2012:

carol7777, thank you very much for reading and commenting! :)

carol stanley from Arizona on September 14, 2012:

Excellent hub on this condition. You covered every aspect. I knew of several women who had this. All okay now. Thanks for a great hub and really well researched information. Voted UP.