Learn more about the causes and complications of gestational diabetes, plus steps you can take to prevent it.
What is gestational diabetes?
Gestational diabetes mellitus (GDM) is a temporary form of diabetes that is diagnosed during pregnancy (gestation), usually between weeks 24 and 28, and affects about 4 percent of all pregnancies, according to the American Diabetes Association. Gestational diabetes means that your blood sugar (also called blood glucose) is too high. In most cases, your blood sugar will return to normal soon after delivery. However, too much glucose in your blood during pregnancy can increase your risk of developing type 2 diabetes later in life and can also cause future health problems for your baby.How does gestational diabetes occur?
The placenta, the organ that transfers hormones and nutrients from you to your baby via the umbilical cord, is responsible for your baby's growth and development. Hormones in the placenta block the action of your insulin, a regulatory hormone that controls the amount of glucose in blood. This dilemma, called insulin resistance, forces the pancreas to produce up to three times as much insulin for the body to function properly. Normally, you body is able to meet this challenge and your blood sugar levels normalize. Gestational diabetes occurs when your body doesn't produce enough insulin during pregnancy to combat insulin resistance, resulting in high blood sugar levels, or hyperglycemia.What are the signs of gestational diabetes?
For most pregnant women, gestational diabetes does not cause any noticeable physical symptoms. When gestational diabetes symptoms do occur, they are usually mild and not life threatening. These include:· Blurred vision
· Fatigue
· Frequent infections
· Increased thirst
· Increased urination
· Nausea and vomiting
· Unexplained weight loss
How does gestational diabetes affect you and your baby?
Because gestational diabetes develops later in pregnancy, after your baby's organs have formed (around week 13), it does not pose the risk of serious birth defects that can occur earlier in pregnancy. Most women are able to control their blood sugar without causing any harm to themselves or their baby. However, poorly controlled blood sugar can cause complications for both you and your baby.Complications of gestational diabetes in babies:
· High birth weight. When you have gestational diabetes, your body produces extra insulin to control your high blood sugar (glucose), but the insulin doesn't lower your blood sugar level sufficiently. While insulin does not cross the placenta, glucose and other nutrients do. This causes your baby to have high blood glucose levels as well, forcing the baby's pancreas to make extra insulin to transport the glucose out of the blood stream and into the cells. Once in the cells, this extra glucose is stored as energy in the form of fat, causing your baby to grow too large (macrosomia).
· Delivery complications and increased risk for cesarean section (C-section). Sometimes babies develop shoulder dystocia, meaning their shoulders have gotten so large that regular delivery is difficult. This, along with increased birth weight, makes the need for delivery by C-section more likely.
· Low blood sugar at birth. Your baby is more likely to have low blood sugar during the first few days of life, as it will no longer be receiving excess blood sugar from you.
· Preterm (early) labor. Your high blood sugar may increase your risk of going into labor early and delivering your baby before its due date.
· Breathing problems. Babies born early may experience respiratory distress syndrome - a condition that makes breathing difficult. Babies with this syndrome may need help breathing until their lungs become stronger.
· Increased risk for obesity and type 2 diabetes in childhood and adulthood.
Complications of gestational diabetes in mothers:
· Increased risk for type 2 diabetes later in life. About 20 to 25 percent of women who have had gestational diabetes will develop type 2 diabetes 5 to 10 years down the road. Obese women who had gestational diabetes run an even greater risk of developing type 2 diabetes. Women with gestational diabetes should get their blood sugar tested for type 2 diabetes every few years after the birth of their child.
· Increased risk of gestational diabetes in future pregnancies. Women who have previously had gestational diabetes have a 66 percent chance that it will recur in a future pregnancy.
· High blood pressure. Women with gestational diabetes have an increased risk of developing high blood pressure (hypertension) later in life.
· Preeclampsia. Preeclampsia is a syndrome characterized by high blood pressure, protein in the urine and swelling in the legs and feet. Preeclampsia raises the risk of developing eclampsia, a rare but emergency medical condition.
· Increased risk for miscarriage or stillbirth if gestational diabetes goes untreated.
What are the risk factors for gestational diabetes?
Women who fall under any of the following criteria are at higher risk for developing gestational diabetes:· Overweight or obese before becoming pregnant
· Family history of diabetes (parent or sibling)
· Have prediabetes
· Have high blood pressure (hypertension)
· Over the age of 25 during pregnancy
· Hispanic, Black, Native American or Asian
· Had gestational diabetes during a previous pregnancy
· Previously gave birth to a baby that weighed more than 9 pounds
· Have glucose in your urine during a routine prenatal screening
· Had a previous unexplained miscarriage or stillborn baby
According to the National Institute of Digestive and Diabetes and Kidney Diseases (NIDDK), you are considered at:· High risk for gestational diabetes if you are very overweight, have had gestational diabetes before, have a strong family history of diabetes, or have glucose in your urine during a routine prenatal check;
· Average risk if you have one or more of the risk factors from the list above;
· Low risk if you do not have any of the risk factors from the list above.
If you are at average or high risk, talk to your doctor about being tested for gestational diabetes.How is gestational diabetes screened and diagnosed?
Women at high risk should be screened for gestational diabetes at their first prenatal exam. Women at average risk should have a screening test during weeks 24 to 28 of their pregnancy. If you are at low risk for gestational diabetes, your doctor may decide that you do not need to be tested.There are various tests that you can take to be screen for gestational diabetes. These include:
· Fasting blood glucose test (or random blood glucose test): A test of your blood sugar level following an initial 8-hour fast in which no food or drink except water is permitted.
· Glucose challenge test: This test involves drinking a sugary liquid after an initial 8-hour fast and then having your blood glucose level tested 1 hour later. A blood sugar level above 140 mg/dL (milligrams per deciliter) indicates potential gestational diabetes. In these cases, a follow-up oral glucose tolerance test is performed.
· Oral glucose tolerance test (GTT): After an 8-hour fast, your blood sugar level will be tested. You will then be asked to drink a sugar liquid and then have your blood glucose tested once an hour for three hours. If two of these blood glucose tests are higher than normal, gestational diabetes is diagnosed.
How is gestational diabetes managed and treated?
Treating gestational diabetes means taking steps to keep your blood sugar levels in a healthy target range. To do this:· Monitor your blood sugar levels in the morning and after meals.
· Eat a healthy, balanced diet to control blood sugar and avoid excessive weight gain. Distribute meals evenly throughout the day and restrict sugar intake. Most women with gestational diabetes meet with a dietitian or diabetes educator to create an individualized gestational diabetes diet.
· Try to exercise at a moderate level every day. Exercise forces cells to release glucose, naturally lowering blood sugar. Make sure to check with your doctor before starting a workout routine if you have been previously inactive.
· You may need to take insulin. About 15 percent of women with gestational diabetes will require insulin injections to lower blood sugar levels. You will give these shots to yourself one to three times daily. Insulin is not harmful to your baby; it cannot cross through the placenta into your baby's bloodstream.
· Close monitoring of the baby is crucial, especially if you are taking insulin injections. The doctor should perform ultrasounds and other tests to make sure the baby is healthy.
The NIDDK provides the following chart of blood glucose targets for most women with gestational diabetes. Talk with your doctor about whether these targets are right for you.| Upon awakening | Blood glucose not above 95mg/dL |
| 1 hour after a meal | Not above 140mg/dL |
| 2 hours after a meal | Not above 120mg/dL |
How can I prevent gestational diabetes?
Healthy lifestyle habits like eating healthy foods, staying active and losing weight before pregnancy go a long way in helping prevent the development of gestational in women who aren't at high risk.These healthy habits may also reduce your risk of having gestational diabetes during your future pregnancies and also reduce your risk of developing type 2 diabetes down the road.
