Diabetes is one of the most common diseases in the U.S., affecting more than 30 million people. When it develops during pregnancy, the condition is called gestational diabetes –and the rates of gestational diabetes are increasing. Research published in JAMA Network shows that gestational diabetes rates increased from 4.8% to 6.4% between 2011 and 2019. The study included more than 12.6 million women ages 15-44 women who were having their first baby.
This is alarming, because gestational diabetes used to be more prevalent in older pregnant women—now we are seeing it more frequently in younger patients.
Gestational diabetes develops when the placenta secretes a hormone called human placental lactogen (HPL). This hormone is important for fetal growth as it causes an increase in maternal glucose (sugar) levels that then pass to the baby.
When women with gestational diabetes don’t get the care they need, expectant mothers and their babies are exposed to health problems. Women with gestational diabetes are at an increased risk of developing Type 2 diabetes later in life, needing a C-section, or developing high blood pressure in pregnancy (preeclampsia).
Potential effects on the baby include an increased risk of:
- Birth trauma: The most common type is nerve injury from shoulder dystocia, or when the baby’s head delivers but the shoulders remain lodged behind the mother’s pubic bone
- Jaundice: An excess of bilirubin (a yellow pigment released by red blood cells) in the baby’s blood
- Neonatal hypoglycemia: Low blood sugar at birth
Women who are at risk for diabetes – or those whose blood sugar levels are higher than the average person prior to pregnancy – are most likely to develop gestational diabetes. This often includes women with obesity, as well as those with a strong family history of diabetes.
Maintaining a healthy weight and lifestyle, including regular exercise, will help control your blood sugar before pregnancy, and is the best way to reduce the risk of gestational diabetes. Because we do not generally recommend weight loss during pregnancy, treatment typically focuses on eating nutritious foods and use of medications to lower blood sugar as needed.
I had a patient in her early 40s who, after two decades of trying to conceive, was having her first baby. She had pre-diabetes before pregnancy and developed gestational diabetes during. Because she diligently followed a diabetes-friendly eating plan during pregnancy, she ended up having a beautiful, healthy baby. It takes commitment, but it is very doable.
Lowering your blood sugar
Before pregnancy, nutrition and weight management play a key role in reducing gestational diabetes risk. Data from the Centers for Disease Control and Prevention show that in 2000, approximately 30% of U.S. adults had obesity. In 2018, the number jumped to 42%, including 40% of people age 20 to 39. The increase in gestational diabetes cases is, in part, a symptom of our country’s overarching obesity epidemic.
During pregnancy, follow a diabetes-friendly eating plan that emphasizes protein and avoids carbohydrates and sugar. Eating three small to moderate-sized meals and two to four healthy snacks per day can help stave off cravings and keep you feeling full.
Women who follow this regimen generally experience a drop in their blood sugar levels and, ultimately, healthy deliveries. You don’t have to make separate meals for yourself – encourage your whole family to start eating healthier.
Eating a diabetes-friendly diet is the key to managing gestational diabetes. These diets typically emphasize protein and avoid carbohydrates and sugar.
Talk with your Ob/Gyn about how a nutritionist can create a complete diet plan if you test positive for gestational diabetes. We can connect you with community resources if you need help accessing healthy foods.
Patients with gestational diabetes should check their blood sugar levels four times a day with a glucometer, a small blood sugar reader that provides instant results. The American Diabetes Association suggests these guidelines for healthy blood sugar levels:
- Before meals: 95 mg/dL or less
- One hour after meals: 140 mg/dL or less
- Two hours after meals: 120 mg/dL or less
If eating differently isn’t helping, we might prescribe insulin to treat high blood sugar. Insulin is safe and effective, and it doesn’t affect the baby’s development. There are diabetes pills as well, such as metformin. However, their long-term effects for pregnant patients and their babies have not been studied in large-scale clinical trials.
After delivery, it is important to keep managing your blood sugar. Having gestational diabetes doubles the risk that you will develop Type 2 diabetes later in life. In many ways, gestational diabetes is like a test drive of your future health – you can experience the condition and still have time to make healthy changes.
Diabetes is a top risk factor for heart disease, which is the leading cause of death in the U.S. Uncontrolled diabetes also can damage the eyes, kidneys, and nerves.
Related reading: Erica's pregnancy story: Heart attack at 31, baby at 36
How we diagnose gestational diabetes
We typically test for gestational diabetes between 24 and 28 weeks of pregnancy, but we might check earlier if patients have risk factors.
The most common technique we use to diagnose gestational diabetes is the two-step glucose challenge test. Patients drink a small bottle of sugar solution and have their blood sugar checked an hour later. If your blood sugar is high, you’ll be asked to take a three-hour glucose tolerance test a week or so later. This longer test requires that participants fast beforehand. If the second test shows high blood sugar levels, we diagnose gestational diabetes.
Some providers use the one-step glucose challenge test instead, in which patients drink the sugar solution and have blood drawn a total of three times over two hours. The idea is to potentially spot more cases of gestational diabetes.
However, a study published in the New England Journal of Medicine found that although the one-step testing identified nearly double the cases of gestational diabetes, there were no significant differences in outcomes such as large babies at birth, preeclampsia, and primary cesarean (C-section) delivery among the two-step group.
The preferred testing is the two-step approach, but it’s what you do with the information after the diagnosis that can make a difference in your health and pregnancy outcomes.
When women can manage gestational diabetes with a healthy diet and medication (when it’s needed), they typically deliver their babies with no setbacks. Talk with your doctor if you have or are concerned about gestational diabetes. We’ll discuss your options and connect you with the support to achieve a happier, healthier pregnancy.