The glucose tolerance test offered in the 24th to 28th week of pregnancy is hated by moms-to-be the world over.
If you’re not familiar with the test, it involves drinking a solution of 50g fast-acting carbohydrate and then testing your blood sugar an hour later (which is why this test is often referred to as the “one hour test”). If the resulting blood sugar number is high, you’re called back for a second, more challenging test (the “three hour test”) where you drink a 100g carb solution and have your blood sugar tested once an hour for–you guessed it–the next three hours.
Apparently the glucose drink for this test tastes like flat soda and can make you feel pretty nauseated, but I wouldn’t know. I already have type 1 diabetes—the autoimmune kind, not caused by, reversed by, or related to diet, lifestyle, or pregnancy--so I never needed to take the glucose challenge test myself. But just about everyone I know who has taken it has expressed quite a bit of displeasure with the experience.
In recent years, the glucose challenge test has become even more despised after food activists pointed out that the glucose solution you’re supposed to drink is toxic. You might have seen this image in your mom groups:
If I’m honest, this often-shared infographic makes me a little cringe-y.
Because it doesn’t tell the full story.
Because of this image, I have seen many moms in my groups decline gestational diabetes testing altogether, or ask their doctor or midwife–neither of which specialize in diabetes–to do alternative blood tests that are not reliable diagnostic tools.
I’m not here to argue about the merits of the glucose drink. I’m not here to tell you that you should or should not drink it.
But I am here to say that being tested for gestational diabetes is extremely prudent, that there are ways to do it that don’t involve the drink, and that you may need to be your own advocate for diabetes management in pregnancy.
To understand why this is all so important, let’s first start here:
CRASH COURSE: WHAT IS GESTATIONAL DIABETES?
Insulin is a hormone produced by the body that allows glucose–an important energy-providing sugar–to move from the blood to inside the body’s cells, where it is used for energy. Without enough insulin, glucose accumulates in the blood rather than going where it’s needed.
In the second and third trimesters of pregnancy, your placenta is fully formed and begins to release necessary hormones that have the side effect of making you insulin resistant. This means that in pregnancy, your body needs to make extra insulin to keep your blood sugar in the proper range (normal glucose ranges from about 70 mg/dL to roughly 140 mg/dL).
It is normal for a healthy woman’s insulin needs to double or even triple throughout the course of her pregnancy.
When the body can’t keep up with the increased insulin demands of pregnancy, mom’s blood sugar will rise, and she is said to have gestational diabetes. In pregnancy, elevated blood sugars caused by gestational diabetes can result in, among other things:
• Excessive birth weight (which increases the risk of birth complications, birth injuries, and C-sections)
• Preterm (early) birth
• Respiratory distress syndrome (serious breathing difficulties)
• Low blood sugar at birth (a result of baby’s body producing extra insulin in utero to combat the high-sugar environment of mom’s body; when baby is born, the extra insulin remains in baby’s system for a time and causes the blood sugar to drop too low–in extreme cases, causing seizures)
• An increased risk of obesity and type 2 diabetes later in baby’s life (about 50% of moms with gestational diabetes go on to develop type 2 diabetes later in life themselves)
• Additionally, moms with gestational diabetes are at increased risk for preeclampsia (high blood pressure), polyhydramnios (excessive amniotic fluid that increases the risk of preterm birth and fetal malposition), birth interventions (induction, epidural, vacuum or forceps assisted delivery, etc.) and Cesarean birth.
Now that you know what gestational diabetes (GD) is and the problems it can cause, here’s what else you need to know:
MYTH #1: IF YOU ARE OTHERWISE HEALTHY, YOU DON’T NEED TO BE WORRIED ABOUT GESTATIONAL DIABETES
Certain risk factors–being overweight or obese, physical inactivity, a history of PCOS, diabetes in an immediate family member, previously delivering a baby over 9 pounds, etc.–put you at increased risk for developing gestational diabetes (source).
But these risk factors don’t guarantee anything.
I have a friend who didn’t develop GD with her previous two pregnancies, who is a physically active runner completing 10Ks in her first and second trimesters, who has no family history of diabetes, and who maintains a healthy diet and a normal BMI. She developed GD with her third and fourth pregnancies regardless.
Meanwhile, around the same time, another friend of mine didn’t develop gestational diabetes even though she started her pregnancy morbidly obese, gained an additional 100lb while pregnant, and has an extensive family history of type 2 diabetes.
Routine testing for GD became the standard precisely because diabetes doesn’t discriminate. Not having risk factors doesn’t mean you won’t get it. Likewise, having risk factors doesn’t mean you will.
MYTH #2: YOU’LL BE ABLE TO TELL IF YOUR BLOOD SUGAR IS HIGH, SO TESTING IS UNNECESSARY
Someone once told me she “would know” if her blood sugar was high during pregnancy because she could feel high blood sugars.
While it is true that some people can feel high blood sugars, the blood sugar usually has to be VERY high before this happens. If you do not have pre-existing diabetes, you will by definition have never experienced a blood sugar high enough to feel. Because your pancreas works!
And while it is true that some people will experience high blood sugar symptoms of increased thirst, urination, and fatigue, not everyone does.
Before being diagnosed with type 1 diabetes, I had been walking around with an average blood sugar of 250 mg/dL for months without feeling any symptoms. Not to mention that increased thirst, urination, and fatigue are already pretty normal symptoms of pregnancy for most women in their second and third trimesters!
But what about the urine tests, you ask? You know, when you go to your OB and they make you pee in a cup every appointment? Don’t those check for signs of diabetes?
They do! Unfortunately, your blood sugar has to be over about 170 mg/dL before glucose spills into the urine (source), and sometimes blood sugar has to be very high (300+) for an extended period of time before the urine will contain signs that the body is not using insulin appropriately.
In the absence of proper testing, it can be very difficult to tell if your blood sugar is high. And sometimes blood sugars just 20-50 points above normal can affect a pregnancy (source).
MYTH #3: YOU SHOULD SKIP THE GLUCOSE TEST, BECAUSE THE DRINK IS BAD FOR YOU
Okay, I said I wasn’t going to argue that you should or should not drink the glucose drink (aka “glucola”). And I’m not going to. You will need to decide for yourself the merits of this particular beverage and whether or not you want to drink it.
However, I will say that I take issue with calling it “toxic” and “dangerous.” As a result of this messaging, many women are opting to forego gestational diabetes testing completely, and we’ve already discussed how that can potentially be a huge problem.
It’s worth noting that brominated vegetable oil (BVO), one of the objectionable glucola ingredients, was found to cause serious problems only after people drank between 2 and 8 liters of soda containing it on a daily basis for months at a time (source, source). That doesn’t make BVO safe or healthy, but it does make it a lot less scary considering the glucola drink is just 10oz of liquid–just a little bit more than 1 cup.
The drink is also commonly criticized for containing “too much sugar,” and indeed: 50g sugar/carb does seem like a lot.
But don’t forget: ALL carbohydrates are converted to sugars–usually glucose–that raise blood sugar. In other words, when you’re looking at nutrition labels, the number that matters is “Total Carbohydrate,” not “Total Sugars.”
The truth is, 50g carb is actually right around what most dietitians recommend the average person consume per meal, and most people eat more than 4 times this many carbs in a day, often without realizing it.
So before you think GD testing isn’t necessary because you “never eat that much sugar,” you may need to take a closer look at the actual carb content of your diet. Carbs are hidden in foods, sauces, and drinks you might not expect in quantities that might surprise you.
For perspective: Do you have plans to consume dates while pregnant for their birth-aiding benefits? If so, just six dates (the daily recommended amount according to some studies) contain about 90g of carb. And natural sugars–in the absence of fat, fiber, or protein–will raise your blood sugar much the same way the glucola will.
Now again, I’m not arguing that the glucola drink is healthy, or that you should get your carbs from the simple sugars found in the drink. The good news is you can use an alternative beverage or food to do your glucose challenge test.
If you have concerns about the drink, skip the drink! But don’t skip the test entirely. Use some other food or drink that measures out to 50g carb instead.
If you’re used to eating a low carb diet (less than 150g a day) or rarely consume fruit or other fast-acting carbs, consider asking your provider if you can simply manually test your blood sugar upon waking up and 1-2 hours after eating over the course of about a week. To be honest, this will probably give you the most accurate picture of how your body responds to the food you eat anyway.
During your pregnancy, if you want, you can follow a “diabetic diet” as a “just in case.” A “diabetic diet” is really just a normal, healthy diet with a carbohydrate recommendation moderately below the standard recommendation. But be advised: For many moms, diet and exercise alone is not enough to manage high blood sugars in pregnancy, and sometimes medication becomes necessary. The only way to know if you are one of those moms is to do some kind of test.
PRO TIPS (brought to you by my 12 years experience with type 1 diabetes): 1) Fat and protein slow the rate at which sugar enters the blood. For the glucose challenge test, you ideally want to use fast acting carbs and keep fat and protein to a minimum. Organic jelly beans, apple juice, and orange juice are good options. 2) If you opt to manually check your blood sugar via finger pricks, poke the sides of the finger tip rather than the pad. It hurts less when you do it this way!
READ MORE: How To Plan For A High Risk Pregnancy
MYTH #4: YOUR DOCTOR/MIDWIFE CAN DO A BLOOD DRAW INSTEAD
Yes, they can! But I wouldn’t bother asking them to. Here’s why.
The blood draw in question is probably for a hemoglobin A1c test. This test gives you a percentage that corresponds to an estimate of what your average blood sugar over the past three months has been. But there are a few problems with this.
First of all, due to factors (like increased blood volume and decreased red blood cell lifespan) during pregnancy, pregnant moms will come back with A1c percentages that are artificially low (source, source). I personally experienced this in both of my pregnancies: My A1c dropped from 5.8 to 5.1 even though nothing about my daily level of glucose control actually changed.
Furthermore, the A1c test is not precise. An A1c result of 6.8 might come back anywhere from 6.4 to 7.2 if the test is ran again on the same blood sample (source).
And don’t forget that the A1c test estimates your average blood sugar over the last three months. High blood sugar caused by gestational diabetes doesn’t typically start to happen until weeks 24-28. So a test that estimates your blood sugar levels in the three months before your blood sugar would have even started rising? You can see why that test result wouldn’t be super helpful: It doesn’t actually tell us much about how your body responds to food right now.
According to the National Institute of Health and other research, the A1c test should not be used to diagnose gestational diabetes (source, source). A provider’s willingness to order the blood draw does not, unfortunately, make the test a reliable diagnostic tool.
MYTH #5: IT IS YOUR FAULT IF YOU GET GESTATIONAL DIABETES
No, it’s not.
Diabetes of any kind is highly stigmatized. People assume if you have it, your poor choices are to blame. Very often–most often, in fact–this is not the case, even though the media and people who don’t understand diabetes will suggest otherwise. Please don’t let the ignorance of others get to you!
A gestational diabetes diagnosis can be overwhelming, but it is fortunately short-lived. Because gestational diabetes goes away after pregnancy! Once the placenta is delivered, the hormones that cause insulin resistance will go away too.
But here’s the deal: You more than likely won’t know you have gestational diabetes if you don’t get tested.
If you don’t feel comfortable drinking glucola, don’t drink it! There are plenty of good alternatives you can use instead.
Best of luck mama! You got this.