Bump & Beyond | Glucose Tolerance Screening

Glucose Tolerance Screening in Pregnancy

In the second trimester of your pregnancy, around 24 weeks, your Obstetrician (OB) will schedule you for an appointment to take a glucose tolerance test. This screening is used to determine if you have gestational diabetes.

Gestational diabetes is a condition in pregnancy that occurs when your body can’t regulate its blood sugar levels. Gestational diabetes comes with risks for both mom and baby, so getting a timely diagnosis is important. Up to 10% of pregnant women in the U.S. develop gestational diabetes, according to the Centers for Disease Control and Prevention (CDC). Left untreated, gestational diabetes can lead to some potentially dangerous consequences for both mom and baby.

My Experience with Glucose Screening

In my first pregnancy, I completed the one-hour glucose screening, which does not require prior fasting. My OB’s office provided me with a 50-gram glucose drink and drew my lab work exactly one hour later. The next week, I got the news that I passed the test! However, in my second pregnancy, I unfortunately did not pass the initial one-hour screening and needed to complete the three-hour glucose screening. Nearly 25% of women do not pass the initial glucose tolerance screening, and I was one of them.

The Three-Hour Glucose Screening - What to Expect

The three-hour screening is more comprehensive and requires you to fast beforehand. I highly recommend making a morning appointment so you are less likely to feel sick from fasting. The lab instructed me to fast starting at midnight the night before, excluding water. To complete the screening successfully, you must not eat or drink — even water — after drinking the glucose drink, and you must not throw up the drink during the three-hour window. This is a tough task, but it is important to ensure accurate results. For this screening, the glucose drink is 100 grams, and your blood is drawn four times.

• The screening starts with a fasting sugar blood test
• Then you have five minutes to finish your glucose drink – bottoms up
• Then a blood test at one hour
• A two-hour blood test
• And finally a three-hour blood test

I was fortunate that my mom could come with me that day and keep me company. To make the test more pleasant, here are some things I would recommend:

• Take a short stroll outside if you are able. It helps pass the time and distract from the initial nausea after drinking the sugary drink. Some fresh air is welcome when you aren’t feeling well!
• Have a fully charged phone
• Bring earbuds and watch a show or movie
• Pack a book or e-reader
• Have your partner, family, or friend come with you to drive in case you don’t feel well after completing the test. This is also great for moral support!
• Have a water cup or bottle prepared for when you finish the test. I was thirsty and ready to get the taste of the drink out of my mouth when I completed the test.

The following week I found out that I passed the three-hour test! If you fail the three-hour glucose screening, try not to worry. Proactive monitoring and treatment can help ensure you and your baby stay healthy and safe throughout the remainder of your pregnancy. Your physician will also be there to support you in navigating gestational diabetes.

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