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Pregnancy: Glucose Test

There are a lot of tests during pregnancy. Some of them are just fine, and others don't feel the greatest. One that is a common test for a doctor to give between 24 and 28 weeks is a glucose screen test, sometimes referred to as a 1 hour glucose test. In this test you will drink 50 g of glucose in a 10 ounce liquid form. After an hour you will have your blood drawn to see how your body did with the bombardment of sugar. If your blood sugar levels are about 140 then your doctor will order a glucose tolerance test, or a 3 hour glucose test. This can bring about a lot of feelings and worry. But knowing the facts can help you make it through the testing and waiting process.

The Test

With a three hour glucose test (or a glucose tolerance test) you will be asked to fast all foods after 12am and take the test in the morning. You will be allowed to have a small amount of water before the test, but that's it. You are also not allowed to smoke or have caffeine of any sort before the test. The test will follow the following pattern:

  1. Your fasting blood sugar will be measured by drawing your first blood sample.
  2. You will be asked to drink a 100g glucose drink (in 10 ounces). This can be a little harder then it sounds since you have only five minutes to do it.
  3. You will have your blood drawn after 1 hour, 2 hours, and 3 hours.

This gives the doctors 4 numbers to work with. It also means that you will need to sit in the lobby area for three entire hours while waiting for the test to be over. During this time you will be asked not to eat, drink, or even chew gum. You will also begin to feel some of the side effects of the glucose.

The Side Effects

Every woman is different, which could mean that you could have no problem taking the sugary drink down and keeping it there without feeling yucky. However, these are some of the possible side effects and how I felt both times I have had to do the three hour glucose test. Some of these symptoms are present with the 1 hour glucose screen, but not as strong or as likely.

  • Nausea- Having that much sugar down there makes you nauseous. This seems to last for a long time on and off.
  • Vomiting- Some women throw up (I did the first time). This is okay as long as the drink has been down there long enough. Otherwise you have to come back another day to start over. Each lab has to decide if it has been long enough, but in my case it had been about an hour and a half and I didn't have to start over. This last time I got sick after a nap at home. So, it can last a long time.
  • Headache- The headache is not an easy one to handle. It hurts a lot, particularly in the front of you head. This is probably because of the sugar and the lack of water. You are double dosing yourself for a rough time. Try to drink lots of water when you are done to get rid of the headache as fast as possible.
  • Tiredness- The test leaves you feeling tired. Not only is your body working hard to make a baby, but you are working hard to process a lot of sugar. Overall a nap is something most consider a good idea after such an event.
  • Achy Body- After the nap, you may feel achy and sore. This too is from all the sugar and possibly dehydration. Make sure you work on getting your water in.

The Worry

This test always makes me feel a little worried as well. There are lots of moms talking about it on mommy boards, so it is fairly normal to feel worry when you are told that the screening (1 hour test) was high. Many are sure that this means that they have gestational diabetes and that it means a lot of other bad things. However, it should be noted that "failing" the screening doesn't mean a whole lot.

My story- Every now and again a personal story makes a difference. In this case I "failed" the first glucose screening. I got 159 on it, which is fairly high. I sat through the 3 hour glucose test, feeling worried and icky. I worried and researched gestational diabetes for four days waiting for results. The doctor called to let me know that all of my numbers were normal and there was no sign of gestational diabetes. That was it. It was over and all that worry had been for no good.

This doesn't mean that it happens to everyone. However, you should know that it happens to some. It could be you. Additionally, even if it doesn't happen to you, it isn't worth the worrying! Worry can make you feel bad and isn't good for your baby either. So, try to sit back and relax. Waiting is always rough, but soon you will know.

The Results

Your doctor probably won't show you your exact results. However, this is how it works. There are four numbers, starting with your fasting blood sugar level. Each number is recorded and then evaluated. Here is what the doctor is hoping for:

  • Fasting: 95mg or less
  • 1st hour: 180mg or less
  • 2nd hour: 155mg or less
  • 3rd hour: 140mg or less

If one of your numbers is high then you doctor will have you repeat the test to make sure that you don't have gestational diabetes. If two of your numbers are high then you will be diagnosed with gestational diabetes and will then have to move on from there.

A Note About Gestational Diabetes

Many women worry about the glucose test because they are afraid that they will be diagnosed with gestational diabetes. In reality, this isn't ideal. However, there are several things that should be noted.

  • Gestational diabetes effects 4% of all pregnant women. You are not alone. In fact, there are about 135,000 cases of gestational diabetes each year.
  • Gestational diabetes doesn't cause birth defects! The high blood sugar becomes a problem later in pregnancy and effect the baby in two major ways. First, extra sugar which crosses the placenta is stored as fat in the baby's body. Second the baby's pancreas works hard to get rid of the extra blood sugar in the blood stream which means that the baby could be born with low blood sugar.
  • Gestational diabetes can and should be treated. The great thing about being diagnosed with gestational diabetes is that you have the chance to follow a treatment plan and help protect your baby. Treatment includes a diet plan and exercise and sometimes includes daily blood sugar testing and insulin shots. However, all of these things can help the baby grow normally and can eliminate the chance of having a Cesarean section that very large babies require.
  • In most cases gestational diabetes goes away at the end of the pregnancy. You will probably have to repeat a glucose tolerance test (the 3 hour one) after 6 weeks. But for most pregnant moms, the diabetes goes away after the pregnancy if over. A few moms find out that they have type 1 or type 2 diabetes and probably had it before they were pregnant.

Keep Worry At Bay

Yes, being diagnosed with gestational diabetes is a bad thing. However, it is also a good thing because it gives you and your doctor the ability to do what's right for your baby. Treating your gestational diabetes is what is best for you and your baby. This can mean a healthier pregnancy, a healthier you, and a healthier start to your baby's life. Finding out now is better then having a very large baby and having your doctor assume that you had the problem but never knew it.

Having a glucose screening (the 1 hour glucose test) is normal. Most doctors request that it be done between 24 and 28 weeks. Having a glucose tolerance test (the 3 hour test) is done if your first one is high (some doctors use 130, though many use 140). It doesn't mean you have gestational diabetes or that there is anything to worry about. It is just the next step to making sure you and your baby are healthy. If you are diagnosed with gestational diabetes you will have to make some changes, but these are best for you and your baby. Don't worry, just go with the flow and make choices that will bring your baby into the world healthy and loved!


Lsmithm on April 02, 2014:

The only problem I have with the administration of the 50g test in the US is that fasting is NOT required. Other jurisdictions that I researched DO require fasting. Why would they control for the amount of glucose that you drink, but not control for the amount of glucose you took in just prior to the test. It doesn't make sense.

That's why when I failed my 50g test (164ml/dL was my reading), I asked to repeat the screening while fasting, rather than be subjected to what I feel is an archaic way to treat pregnant women (try eating an entire package of oreos to get the same quantity of glucose, or even more than a package... I did the calculations). I was denied the repeated screening, then subsequently shamed into taking the 100g test, which I REFUSED.

Instead, I went to CVS and bought some diabetic testing supplies. I persuaded my doctor to look at my testing log (7x more accurate as I'm self-checking 7 days in a row, and more valid for my individual case because it uses actual food sources in the amounts I normally consume). Time consuming for myself and the doctor? Yes. A better choice for myself and my baby than drowning myself in glucose unnecessarily. Yes. It all comes down to money, ladies. No way would insurance cover that type of diagnostic, so they prefer to drown us and our babies in glucose instead.

Not to mention, these tests have only become standard for almost all pregnant women since 2001. There is now a stigma attached to having a "large" baby over 8-9 pounds, as scientists are trying their hardest to prove that it resulted from the "epidemic" of gestational diabetes. They are even trying to FURTHER lower the accepted thresholds to put MORE women into the GD category. If you don't believe me, read all about it here: www.evidencebasedbirth.com. She attended the most recent conference on gestational diabetes and some doctors are already going to using the new readings. The new test will be 75g only, as well as 3 blood draws FOR EVERYONE. No screening, and only 1 high reading is needed for a GD diagnosis. Most labs seem to be taking a cautious wait-and-see approach, because it's widely accepted that this will cause health care costs, time spent per patient, and of course the number of GD diagnosed women to rise.

Women will always have to stand up for what they believe is best for them and their babies. Medical science is constantly coming up with new edicts that contradict common sense- always enter in with a healthy dose of skepticism and the willingness to research things yourself so you can be an informed medical consumer.

torrilynn on December 20, 2013:

I never knew that you had to take a glucose test when you are pregnant. thanks for the useful information.

Megan Mary on February 21, 2012:

I just took mine today. The drink isn't horrible, just really sweet. In the first hour after I felt a little jittery but it actually helped my hunger growls go away. And surprisingly I did not get a headache from lack of caffeine. I have migraines so I was expecting a migraine. In the last 20 min. I was starting to get hungry again. I brought a baggie with some plain almonds in it for after which helped. I am going to eat with diabetes in mind no matter what the results.

When I got home I poured a cup of coffee and now I am actually hot and sweating and my hands are shaking. So I would say be careful with that cup of coffee after if you drink coffee. I am also about to start drinking water too to help this. Maybe it would have been better to have some water first.

GoldenGirl on August 18, 2011:

Thanks for the post! Very helpful info, as I had my test done yesterday and still feel icky. Probably the result of not drinking enough water... I was starting to get worried since I hardly ever get headaches!

Sun-Girl from Nigeria on May 18, 2011:

Awesome hub which is well shared,Enjoyed this great article of yours a lot.

tasksgirl from Los Angeles, CA on May 12, 2011:

lol that stuff definitely tastes nasty! I don't even like drinking soda!

tectonic from Singapore on February 19, 2011:

Superb hub you have provided .

Great job!

LondonGirl from London on May 16, 2009:

I had a glucose tolerance test. In the UK, it's slightly different. They don't do the 1 hour one, they go straight for fasting, 1 hour, 2 hour tests. Fortunately, mine was fine.

The thing women who have gestational diabetes have to be aware of is that it's a major warning flag. Some horribly high % of them will get Type II diabetes within 10 years.