Gestational diabetes is a condition marked by high blood glucose (sugar) levels that are discovered during pregnancy. It is defined as carbohydrate intolerance. About two to 10 percent of all pregnant women in the U.S. are diagnosed with gestational diabetes.
These factors increase your risk of developing diabetes during pregnancy:
Keep in mind that half of women who develop gestational diabetes have no known risk factors.
Gestational diabetes is caused by some hormonal changes that occur in all women during pregnancy. The placenta is the organ that connects the baby (by the umbilical cord) to the uterus and transfers nutrients from the mother to the baby. Increased levels of certain hormones made in the placenta can prevent insulin—a hormone that controls blood sugar—from managing glucose properly. This condition is called "insulin resistance." As the placenta grows larger during pregnancy, it produces more hormones and increases this insulin resistance.
Usually, the mother’s pancreas is able to produce more insulin (about three times the normal amount) to overcome the insulin resistance. If it cannot, sugar levels will rise, resulting in gestational diabetes.
Gestational diabetes is usually diagnosed between the 24th and 28th week of pregnancy (when insulin resistance usually begins). If you have had gestational diabetes before, or if your doctor is concerned about your risk of developing gestational diabetes, the test may be performed before the 13th week of pregnancy.
To screen for gestational diabetes, you will take a test called the oral glucose tolerance test. You quickly drink a sweetened liquid, which contains 50g of glucose. The body absorbs this glucose rapidly, causing blood sugar levels to rise within 30-60 minutes. A blood sample will be taken from a vein in your arm about 30 minutes after drinking the solution. The blood test measures how the glucose solution was metabolized (processed by the body).
If your test results are not normal, you will have a similar type of diabetes test in which you have to fast (not eat anything) before the test. If this second test shows abnormal results, you have gestational diabetes.
Gestational diabetes is managed by:
Based on your blood glucose monitoring results, your doctor will tell you if you need to take insulin injections during pregnancy. If insulin is prescribed for you, your doctor, nurse, or diabetes educator will teach you how to give yourself insulin injections.
As your pregnancy progresses, the placenta will make more pregnancy hormones, and larger doses of insulin may be needed to control your blood sugar. Your doctor will adjust your insulin dosage based on your blood glucose log.
When using insulin, a "low blood glucose reaction," or hypoglycemia, can occur if you:
Symptoms of hypoglycemia include:
Hypoglycemia is a serious problem that needs to be treated right away. If you think you are having a low blood sugar reaction:
If insulin is needed during pregnancy, an insulin injection may be given when labor begins; sometimes, it may be given intravenously (through a vein) throughout labor.
Since insulin resistance generally does not develop until the 24th week of pregnancy, birth defects are not a common complication of gestational diabetes. (Birth defects generally occur during the first 13 weeks of pregnancy.)
Gestational diabetes may increase your risk of developing high blood pressure during pregnancy.
Labor and delivery are generally not affected by gestational diabetes. However, if the baby has grown too large, or if your blood pressure is high, a cesarean delivery may be necessary.
It’s important to carefully control blood sugar levels during labor so that the baby doesn’t develop a high insulin level (because of a high blood sugar level in the mother). If this happens, the baby’s blood sugar can drop very low after birth, since it won’t be receiving the high blood sugar from the mother. A glucose solution (sugar solution) may be given to your newborn.
Your baby’s blood sugar level will be tested immediately after birth. If the blood sugar is low, your baby will be given sugar water to drink, or by an intravenous tube in the vein. Your baby may be sent to a special care nursery for observation during the first few hours after birth to make sure he or she doesn’t have a low blood sugar reaction.
If you had gestational diabetes, there is an increased risk that your newborn will develop jaundice. Jaundice is a yellow discoloration of the skin that occurs when there is bilirubin in the baby’s blood. Bilirubin is a pigment that causes jaundice and is released when extra red blood cells build up in the blood and can’t be processed fast enough. Jaundice goes away rapidly with treatment; one form of treatment is to expose your baby to special lights that get rid of the pigment.
Gestational diabetes does not cause your baby to have diabetes. Your child’s risk of developing diabetes is related to family history, body weight, eating habits, and exercise. Give your baby a healthy start by breastfeeding him or her.
Usually, blood sugar levels return to normal after childbirth because the placenta, which was producing the extra hormones that caused insulin resistance, is delivered. After your baby is born, your doctor will check your blood sugar level to make sure it has returned to normal. Some doctors recommend an oral glucose tolerance test 6-12 weeks after delivery to check for diabetes, and then every 1-3 years.
Women who have had gestational diabetes have a 60% increased risk of developing Type 2 diabetes later in life. Because of this risk, you should have your blood sugar level checked during your regular health checkups. By maintaining an ideal body weight, following a healthy meal plan, and exercising, you will be able to reduce your risk of developing Type 2 diabetes. Breastfeeding your baby may help you lose your pregnancy weight.
In addition, women who have gestational diabetes during one pregnancy have a 40-50% chance of developing diabetes in the next pregnancy. If you had gestational diabetes during one pregnancy and are planning to get pregnant again, talk to your doctor first so that you can make the necessary lifestyle changes before your next pregnancy.
Testing your blood sugar at certain times of the day will help determine if your exercise and eating patterns are keeping your blood sugar levels in control, or if you need extra insulin to protect your developing baby. Your doctor will tell you when and how often to test your blood sugar.
Testing your blood sugar involves the following steps:
Bring your blood sugar readings with you to your doctor appointments. He or she can evaluate how well your sugar levels are controlled, and can decide if changes need to be made to your treatment plan.
Your doctor, nurse, or diabetes educator will show you how to use a glucose meter. He or she can also tell you where to get a meter. You may be able to borrow it from your hospital, as many hospitals have loaner meter programs for women with gestational diabetes.
The goal of monitoring is to keep your blood sugar as close to normal as possible. The ranges include:
Time of test
You may be instructed to check your blood sugar:
Target blood glucose reading
< 95 mg/dL < 140 mg/dL < 120 mg/dL
Here are some goals for healthy eating during pregnancy if you have gestational diabetes:
Every pregnant woman should check with her doctor before beginning an exercise program. Your doctor can give you personal exercise guidelines, based on your medical history. Thirty minutes of exercise every day, or most days, will help manage gestational diabetes.
Since both insulin and exercise lower blood sugar, you should follow these additional exercise guidelines to avoid a low blood sugar reaction:
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 01/26/2016