Gestational Diabetes: What It Is, Causes, Symptoms & Treatment

Each year, gestational diabetes affects between 2% and 10% of pregnancies in the United States, according to federal government figures.

Understanding its causes, symptoms and treatment is key to a healthy experience for the pregnant woman and her fetus.

What is gestational diabetes?

When a woman develops high blood sugar during pregnancy, it is known as gestational diabetes. It typically occurs during the middle of the pregnancy, about 24 to 28 weeks along, according to the Cleveland Clinic. But just because a woman develops gestational diabetes doesn’t mean she had diabetes before conceiving. It also doesn’t guarantee she’ll have diabetes after she gives birth.

“Gestational diabetes is diagnosed in the second or third trimester during pregnancy for a person who did not have diabetes before the pregnancy and is related to the pregnancy,” said Patricia Abernathy, certified diabetes care and education specialist at Saint Anthony Hospital in Chicago.

What causes gestational diabetes?

Abernathy points to a significant difference between type 1 diabetes and gestational diabetes.

“Type 1 diabetes usually happens when a person does not produce insulin in the body and insulin is needed to allow glucose to enter cells. A person with type 1 diabetes must take insulin daily,” she pointed out.

Gestational diabetes, however, is often treated through diet and exercise.

A lack of insulin does not cause gestational diabetes, according to Johns Hopkins Medicine. Instead, it stems from hormones produced during pregnancy that make insulin less effective, a condition called insulin resistance. The good news: Gestational diabetic symptoms are not long-lasting and disappear following delivery.

Although the specific causes of gestational diabetes are unknown, certain risk factors put women at risk:

• Being overweight or obese
• A family history of diabetes
• Having given birth previously to an infant weighing greater than 9 pounds
• Age over 25
• Race (women who are American Indian, Asian American, African-American, Hispanic or Latino, or Pacific Islander have a higher risk)
• Having prediabetes, also known as impaired glucose tolerance

What happens during a gestational diabetes test?

Health care providers conduct two types of glucose tests during pregnancy to check for gestational diabetes. The first is the glucose challenge test, a one-hour screening in which women have blood sugar checked after drinking a sweet liquid.

If the screening results are abnormal, a second test, known as the glucose tolerance test or three-hour glucose test, is ordered for confirmation. This test is more comprehensive, involving multiple blood draws at specific intervals. Additionally, it requires women to fast for several hours beforehand to ensure accurate results.

Related to these tests, your doctor may mention the gestational diabetes range. The Mayo Clinic indicates that a blood sugar level of 190 milligrams per deciliter (mg/dL), or 10.6 millimoles per liter (mmol/L), indicates gestational diabetes. If glucose challenge test results are below 140 mg/dL (7.8 mmol/L), it is usually considered within the standard range.

Gestational diabetes symptoms

Gestational diabetes doesn’t cause any obvious symptoms, according to Stanford Medicine. If your sugar is high, however, you may experience these signs of gestational diabetes:

• Frequent urination
• More hungry or thirsty than normal
• Blurred vision
• Nausea or vomiting
• Losing weight even though eating more

Gestational diabetes treatment

"Pregnant individuals diagnosed with gestational diabetes should start receiving individualized education, care, and support around diet and exercise," Abernathy said. "This includes information about adequate food and nutrition intake and learning about foods containing carbohydrates with recommended daily amounts for meals and snacks. Also important is knowing healthy blood glucose values and monitoring blood glucose as recommended.”

A gestational diabetes diet will typically consist of three small meals daily and two to three snacks. The University of California San Francisco suggests these tips for a healthy diet during pregnancy:

• Measure servings of starchy foods.
• Drink no more than one 8-ounce cup of milk at a time as too much milk can increase blood sugar.
• Limit fruit to one small serving at a time.
• Eat more fiber.
• Eat a well-balanced breakfast
• Avoid fruit juice, sugary drinks, excess sugar and stay vigilant about sugar-alcohols (mannitol, maltitol, sorbitol, xylitol, isomalt) in sugar-free foods. These also contain carbohydrates.

Insulin injections may be necessary if diet and exercise alone can't control your blood sugar levels. While most women with gestational diabetes can manage with other methods, a small percentage may require insulin to achieve their blood sugar goals.

Some health care providers prescribe oral medications for gestational diabetes, but their safety and efficacy compared to injectable insulin are still under debate, according to the Mayo Clinic.

Does gestational diabetes go away?

“For many individuals, gestational diabetes can go away after the baby's delivery," Abernathy said. "Additional screening at four to 12 weeks post-delivery and every one to three years are recommended." That's because having gestational diabetes can increase the risk for diabetes.

About 50% of women diagnosed with gestational diabetes are at risk of developing type 2 diabetes later on, according to the U.S. Centers for Disease Control and Prevention. You can reduce this risk by achieving a healthy body weight after delivery. Proactive monitoring and maintaining a healthy lifestyle can play a vital role in preventing future complications.

Living with gestational diabetes

Living with gestational diabetes requires proactive management, but diet changes and regular exercise are sufficient for most expectant women to control blood sugar levels. Adherence to the prescribed treatment plan is crucial if insulin is necessary to manage the condition.

Consistency in taking insulin as directed by your primary care physician or ob-gyn ensures appropriate blood sugar regulation, reducing the risk of complications and promoting a healthier pregnancy.

SOURCE: Patricia Abernathy, MS, MSW, RDN, LDN, LSW, certified diabetes care and education specialist, Saint Anthony Hospital, Chicago