Diabetes in Pregnancy
What You Need to Know
By Lynsey Caldwell Owen, MD, FACOG
Approximately 22 million adults in the United States have a diagnosis of diabetes mellitus, a disease that affects the way that the body processes glucose, which is generally obtained from the diet. Glucose is the main source of energy for cells within the body. The pancreas makes the hormone insulin, which helps glucose enter the cells so it can be used efficiently. In diabetes, there is either a problem with the body’s production of insulin or the cells’ acceptance of the hormone, which leads to an increase in the amount of glucose in the bloodstream. This can have an affect on almost every organ system if the disease is not recognized and treated. During pregnancy, the placenta releases hormones that may make it harder for some women’s bodies to use insulin. This increase in “insulin resistance” is what causes gestational diabetes, or diabetes of pregnancy.
Even if you have never had a problem with diabetes prior to getting pregnant, it is possible that you could be affected with gestational diabetes. The following risk factors make this diagnosis more likely:
- A strong family history of diabetes
- History of diabetes in previous pregnancies or a previous baby greater than 9 pounds
- Multiple gestation (twins, triplets, etc)
- Hispanic-American, African-American, Native American, South or East Asian, Pacific Islander ethnicity
- Increasing maternal age
Depending on your risk factors, your obstetric provider may recommend screening for diabetes early in pregnancy. If you have a positive screening test in the first or early second trimester, the diagnosis of pre-existing diabetes (before pregnancy) is more likely, as the placenta does not tend to significantly affect insulin resistance until after 20 weeks.
Because many studies have shown that gestational diabetes can develop in women without any risk factors, all pregnant women should be screened between 24 and 28 weeks gestation. Typically, this screening test involves drinking a beverage with a consistent glucose content and then measuring the blood sugar at a prescribed time afterwards. If the results of this test are abnormal, some women will go on to have another diagnostic test, while others will be given the diagnosis of diabetes based only on this result.
If gestational diabetes is diagnosed, the first step is usually meeting with your doctor or midwife to discuss the potential impact of diabetes on your pregnancy. Unfortunately, having gestational diabetes can increase the risks of other complications during pregnancy. These problems include:
- The development of high blood pressure or preeclampsia
- The baby gaining more weight than is healthy, which can lead to complications at delivery and even an increased risk for childhood obesity and diabetes
- Other adverse outcomes for the baby, including stillbirth
Fortunately, most of these risks appear to be related to control of blood sugar and hence, good control can mean that women with diabetes can still have healthy pregnancies. At the time of diagnosis, all women should receive nutrition counseling and instruction on how to eat a “diabetic diet”, which is basically a healthy balanced diet consisting of less fat and simple sugars and more fruits, vegetables, and whole grains. Gestational diabetics will be taught how to use a blood sugar monitor called a glucometer, and will check their blood glucose levels using a small drop of blood from pricking a finger at least four times per day. Many pregnant women are able to control their diabetes with diet alone, but if changes in diet are not sufficient to meet the glucose goals, sometimes oral medications or subcutaneous injections of insulin may be necessary.
Depending on how the diabetes is controlled, your doctor will make recommendations about special testing to monitor baby’s well being and the timing of delivery. The benefits of delivery before the due date or spontaneous labor may outweigh the risks for gestational diabetics.
After delivery, women who were diagnosed with diabetes in pregnancy should undergo testing within a few months to ensure that they no longer have any problems with insulin resistance. While most women do not require ongoing treatment after delivery, the risk of developing diabetes later in life is almost doubled for gestational diabetics. It is important that your primary care doctor is aware of this complication and performs regular screening for diabetes in the future.