Gestational Diabetes Mellitus (PDF)

Gestational Diabetes Mellitus

What is gestational diabetes (GDM)?

Gestational diabetes is a type of high blood sugar disorder that only occurs during pregnancy. Approximately 3-5% of pregnant women develop gestational diabetes. Your body breaks down the food you eat into sugar and other nutrients. The sugar goes into your bloodstream. Your body then uses a hormone called insulin to turn the sugar into energy. During pregnancy, the placenta releases hormones that can interfere with the way insulin works in your body. If this happens, you keep more sugar in your bloodstream because your body is having a harder time converting the sugar into energy.

Who is at risk for gestational diabetes?

All pregnant women at are risk for developing gestational diabetes, but there are many factors that can increase a woman’s risk of developing GDM.

* Certain ethnic groups are at higher risk for gestational diabetes including Hispanics, African-Americans, Native Americans, South or East Asians, and Pacific Islanders.
* Being overweight or obese prior to pregnancy.
* Having relatives who have or had diabetes.
* Being older than 25.
* Having gestational diabetes with a past pregnancy.
* Having a stillbirth.
* Having a very large baby with a previous pregnancy (larger than 8 ½ pounds term birth weight).
* Remember, all pregnant women need to be screened for gestational diabetes regardless of risk.

How is screening for gestational diabetes done?

For women at high risk, an early screen is often done at your first OB visit. All women should be screened for gestational diabetes around 28 weeks of pregnancy.

* One-hour Glucose Tolerance Test: You will be given a sugary drink, 50 grams glucola. One hour after drinking this drink, your blood will be drawn to test the level of glucose in it. You are not allowed to eat or drink (except water) during this test.
* If your one hour glucola test is high, we will recommend you do a Three-hour Glucose Tolerance Test. This test requires you to fast (not eat or drink anything but water) for 12 hours. We will then draw a fasting glucose test. Then, you will be given 100 grams of glucola to drink. We will repeat blood draws for glucose testing one hour, two hours, and three hours after you finish the drink. You are not allowed to eat or drink (except water) during this test.
* If the three hour glucola test has one high value, you will be sent to a registered dietician for nutrition counseling.
* If the three hour glucola test has two or more high values, you will be diagnosed with gestational diabetes. Nutritional counseling and glucose monitoring are recommended.

What do I do to monitor/treat my gestational diabetes?

* You will be sent to a registered dietician for nutrition counseling and to learn how to monitor your blood glucose levels at home with a home glucometer. The dietician and your healthcare provider will help you to monitor your blood glucose levels and ensure your health and the health of your baby.
* Exercise is very important in maintaining appropriate blood glucose levels. It is recommended you get 30-60 minutes of safe exercise activities (walking, swimming, etc) per day. Talk to your healthcare provider about your exercise routine and before starting any new exercises in pregnancy.
* Some women are unable to keep their blood glucose levels at an appropriate level with exercise and diet control alone. If this is the case, you may be started on medication to aid your body in controlling your blood glucose levels. Some people take an oral medication (a pill) and others take insulin injections. Your healthcare provider will discuss these options with you to ensure you are getting the best medication for you and your baby.
* The amount of monitoring done on your baby may increase or change:
o Some women will need to have Non-stress Tests (NST) done one to two times per week. This involves attaching special belts to your abdomen that monitor baby’s heart rate and uterine contractions. This test usually takes between 20 and 40 minutes.
* Many women will have ultrasounds to monitor baby’s growth every 4-6 weeks.
* Other testing may be ordered to monitor your health or your baby’s health; your provider will discuss all testing with you.

What are the risks associated with gestational diabetes for my health and the health of my baby?

Risks for Mom

* You are at an increased risk of developing high blood pressure in pregnancy due to high blood sugars in your body. This could mean you would need to deliver your baby early.

Risks for Baby

* If your blood sugars stay too high, your baby may grow larger than it normally would prior to birth. This could mean your baby’s shoulder or arms could be injured during a vaginal birth or you could need a Cesarean Section delivery.
* Your baby’s lungs and liver may take longer to mature than normal. They should be mature by your due date.
* Your baby’s blood sugar may be low after birth. If your blood sugar is too high during pregnancy, your baby makes extra insulin. When the constant supply of sugar from you ends at birth, the baby may drop his/her blood sugar level.
* In very rare cases, your baby could be stillborn.

The best way to prevent complications of gestational diabetes is to work with your dietician and healthcare provider to control your blood sugars during pregnancy.

What will happen during labor and delivery?

* Your blood sugar will be monitored during labor and delivery. Blood glucose levels go up during times of stress, so you may need medication during labor to keep your blood sugar at an appropriate level, even if you didn’t need medication during your pregnancy.
* Your contractions and baby’s heart rate will be measured.
* Your baby’s blood sugar may be tested after birth.

How do I take care of my blood sugar after my pregnancy?

* Keep your weight at an appropriate level. Your healthcare provider will discuss where your ideal weight should be with you.
* Get regular exercise; a minimum of 30 minutes, 3 times a week.
* Breastfeed. Studies have shown that breastfeeding your baby can help your body utilize insulin better after delivery.
* You should have a Two-hour Glucose Tolerance Test at your 6 week postpartum check. This requires a fasting blood glucose (nothing to eat or drink except water for 12 hours), then you drink a 75gm glucola drink. We then test your blood glucose two hours after you finish the drink. This test is used to ensure that your body has recovered its normal processing of using glucose for energy.
* Have your blood sugar tested every few years, or as often as your health care provider tells you.

Written by the Women’s Group Practitioners Last Reviewed in November 2009
© Copyright 2009 The Women’s Group PC 1