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I Failed My Prenatal Glucose Test. Now What?

When your doctor’s office calls with the news that you’ve failed your first prenatal glucose (blood sugar) test, a flurry of thoughts can start to run through your head.

Did I do something wrong? Does failing a glucose test mean I have diabetes? What do I do after I failed my glucose test?

You might feel disappointed, frustrated and scared. And that’s normal! But a failed glucose test doesn’t always mean you have gestational diabetes, and even if you do, you and your baby can live perfectly healthy lives.

So, while you wait in suspense for your three-hour test, here’s a little advice from our experts about what to expect.

Why do I need a glucose test?

A glucose test during pregnancy checks to see how well your body’s cells absorb sugar. The test measures the amount of sugar in your blood after consuming a specific amount of sugar in a particular time period. A high level of glucose may indicate that you have gestational diabetes.

“Having a glucose test between 24 and 28 weeks of pregnancy is a routine part of prenatal care,” says OhioHealth OB-GYN Sara Alderman, MD. “We also ask patients with an elevated body mass index to do the test either at their initial prenatal appointment or shortly after. By screening early, we can identify women who have preexisting diabetes.”

You may not have obvious signs of gestational diabetes, which is why it’s critical to have regular prenatal care from a doctor. If symptoms are present, they can be mistaken for other symptoms of pregnancy, including exhaustion after eating, urinating more often and feeling more hungry than usual.

What is gestational diabetes?

Gestational diabetes is high blood sugar (glucose) during the second and third trimester of pregnancy. The exact cause is unknown. It may be a combination of factors, including genetics, increased hormones triggered by pregnancy that lead to insulin resistance, and an inability to produce the extra insulin that’s needed to compensate. “By week 26 of pregnancy, women need about two times more insulin than normal to properly regulate blood sugar,” says Alyssa Bixler, diabetes program coordinator at OhioHealth McConnell Heart Health Center. “This need nearly triples by the end of pregnancy. For some women, this demand on the body is too much.”

Alderman says gestational diabetes is fairly common. “Around 10% of pregnant women develop gestational diabetes, and that number is climbing.”

How are the first and second glucose tests different?

The first glucose test is usually a one-hour test that does not require fasting. You will drink a 50-gram glucose drink, wait one hour and then have your blood drawn at your doctor’s office or a laboratory. Results from both tests are available within 24 hours. If your first test results are high, your doctor will request a three-hour glucose test, for which you’ll have to fast and drink a 100-gram glucose drink. You’ll then have your blood drawn after one hour, two hours, and three hours.

Do I need to do anything between my two glucose tests?

Nope! You should go about your life as usual between the two tests. Stressing too much or changing your lifestyle habits can make the results inaccurate.

Are there ways to “pass” a three-hour glucose test?

Some people try to trick the three-hour test to get a passing value by changing their diet. It’s very important that you don’t do this. It can be dangerous for you and your baby. Remember, an abnormal test result is nothing to be ashamed of. It doesn’t mean you’re failing you or your baby. The test just helps your doctor know how to best care for you and your baby during throughout the rest of your pregnancy.

Can you fail your first glucose test and pass your second?

Yes, it’s possible to fail your first glucose test, but not fail your second test. This just means that you probably don’t have gestational diabetes.

What’s considered a high level of glucose in glucose testing?

“Different physicians may use slightly different values to identify patients at risk of having gestational diabetes,” says OhioHealth OB-GYN Sara Alderman, MD. “For the one-hour test, I consider anything above 135mg/dL to be abnormal. If the value is above 200, I assume the patient has gestational diabetes and refer them directly to a dietitian and maternal fetal medicine specialist without requesting the three-hour test.” Alderman says during the three-hour test, the normal range for fasting changes at one hour, two hours and three hours. If a patient has two or more abnormal values during the three-hour test, then the test overall is considered abnormal. Your doctor will likely diagnose you with gestational diabetes if you fail the three-hour test.

How can gestational diabetes affect my baby and me?

Gestational diabetes poses risks to both you and your baby, but with proper treatment during pregnancy, you can both live healthy lives.

  • Risks for baby: Low blood sugar at birth, early birth, large birth weight, jaundice and childhood obesity.
  • Risks for mom: Urinary tract infections, high blood pressure, cesarean section and preeclampsia, a potentially life-threatening condition related to high blood pressure.
  • Risks for both: Difficult or dangerous birth of a larger than average baby and Type 2 diabetes later in life.

Bixler says the risk for Type 2 diabetes increases along with age. It’s more likely to occur in the mother within 10 years after pregnancy, and in her child anytime in adolescence or adulthood. Diabetes is also associated with other metabolic disorders and related conditions like weight gain and heart disease. “Being active as a family and focusing on weight management lowers your risk of developing Type 2 diabetes,” she says.

Are some people more likely to get gestational diabetes?

Bixler says any woman can develop gestational diabetes, but there are some known risk factors. These include:

  • Polycystic ovary syndrome.
  • Being overweight.
  • Being over the age of 30.
  • Having three or more pregnancies.
  • Being of Hispanic, African American, Native American, South or East Asian, or Pacific Island descent.
  • A family history of diabetes.
  • Previous births of babies over 9 pounds.

“It’s important to understand that gestational diabetes is not your fault,” says Bixler. “Stay focused on the treatment, not the cause.”

How is gestational diabetes treated?

“There are five aspects to treatment that can help you manage gestational diabetes,” says Bixler.

  • Diet: A dietitian can help you develop a meal plan that balances carbohydrates, proteins, healthy fats and fiber so you and your baby receive adequate nutrition while keeping your glucose level in check. You might need to change your eating habits a lot, or you might not. You don’t need to stop eating carbs entirely, just choose quality carbs, like whole grains, some fruits, quinoa, milk and yogurt. You should also be careful with desserts, and avoid drinks high in sugar, like soft drinks, flavored lattes, sweet tea and fruit juice. We’ve included an infographic at the of this article with some healthy food swaps you can try!
  • Exercise: Be purposeful with your activity. It doesn’t have to be strenuous, just keep moving for at least 30 minutes a day. Try low-impact exercises like walking or swimming.
  • Monitoring blood sugar: You’ll need to check your blood sugar about four times a day to make sure it stays safe for you and your baby.
  • Regular prenatal care: Your OB-GYN will be a great partner through this process. They may also have you visit a maternal fetal medicine specialist. You doctors will provide you with the extra monitoring and care that you need. “Overall, the total number of appointments will be greater for women with gestational diabetes, unless you are able to manage your blood sugar with diet alone,” says Alderman. “You may have to have additional ultrasounds and nonstress tests, which check your baby’s health, or even deliver earlier than 40 weeks.”
  • Medication: Not every woman will need to take medication, but it does help some women keep up with the extra demand for insulin. Your doctor will determine whether medication is right for you, and how often you will need to have appointments with them to manage it.

Does gestational diabetes go away after pregnancy?

Yes. While there is no way to get rid of gestational diabetes while pregnant, in most cases, it will go away within hours after birth. Your doctor will do a blood sugar test after delivery, and again at six weeks after birth. 

Will gestational diabetes happen again to me?

Having gestational diabetes with one pregnancy increases your chances of having it with subsequent pregnancies. It may not be possible to prevent gestational diabetes, but you can be proactive by monitoring your blood sugar earlier in your pregnancy and establishing healthy habits that will help you manage it.

An OB-GYN can help you better understand gestational diabetes. To find one near you who is accepting new patients, visit OhioHealth.com.

Infographic depicting simple food swaps to control sugar