Gestational Diabetes: What It Is, Why It Matters, and What Happens Next
Gestational diabetes is a condition where blood sugar runs too high during pregnancy. It is one of the most common medical complications we see in pregnancy. The good news is that most patients do very well once it is recognized and managed appropriately.
What is gestational diabetes?
During pregnancy, hormones from the placenta make it harder for your body to use insulin normally. Some patients are able to compensate for that change without much trouble. Others are not, and blood sugar starts to rise. When that happens, gestational diabetes develops.
This does not mean you caused it. It also does not automatically mean you had diabetes before pregnancy. Sometimes it truly develops during pregnancy. Sometimes pregnancy is simply the first time an underlying tendency toward diabetes becomes obvious.
Why does it matter?
When blood sugar is too high in pregnancy, it can affect both mom and baby.
For moms, gestational diabetes is associated with a higher risk of problems like preeclampsia, cesarean delivery, and in severe cases diabetic ketoacidosis, which is a serious blood chemistry problem.
For babies, it increases the risk of miscarriage, birth defects including heart defects, growing too large, shoulder dystocia, newborn low blood sugar, and other complications around delivery.
This is exactly why we take it seriously. Not because every case turns into a major problem, but because recognizing it and treating it appropriately improves outcomes.
What are the symptoms?
Most patients with gestational diabetes have no obvious symptoms at all.
That is important to understand. You cannot reliably tell whether you have gestational diabetes based on how you feel. Some patients may notice increased thirst or urination, but those things are also common in normal pregnancy. This is one of the reasons routine screening matters so much.
How is gestational diabetes diagnosed?
All pregnant patients should be screened with lab-based blood glucose testing, typically between 24 and 28 weeks. Some patients who are higher risk may be screened earlier in pregnancy as well, especially if they are overweight or obese and have additional risk factors. Even if early testing is normal, repeat screening at 24–28 weeks is still recommended.
In the United States, the most common approach is the 2-step method:
Step 1: 1-hour glucose screening test
You drink a glucose drink and your blood sugar is checked 1 hour later.
Step 2: 3-hour glucose tolerance test
If the screening test is abnormal, you come back for a longer diagnostic test. Gestational diabetes is usually diagnosed when two or more values are abnormal on the 3-hour test, although some clinicians pay close attention even when there is only one abnormal value.
The main point for patients is simple: this is diagnosed by blood sugar testing, not by symptoms alone.
What happens if I am diagnosed?
Treatment usually starts with:
nutrition counseling
exercise or movement when appropriate
checking blood sugars at home regularly
Most patients begin with non-medication treatment first. The goal is to keep blood sugars in a healthy range without causing ketosis, while still supporting a healthy pregnancy and appropriate fetal growth. Many practices recommend three meals and two to three snacks per day to help spread out carbohydrate intake and reduce major blood sugar swings.
It is also important to understand that treatment is not just “stop eating sugar.” In reality, it is more about learning how to balance carbohydrates in a way your body can handle during pregnancy.
Lifestyle changes that often help
One of the most effective first steps is regular exercise. We generally recommend 20–30 minutes of moderate to intense exercise most days of the week, with a goal of about 150 minutes per week when appropriate in pregnancy. Exercise helps improve insulin resistance by shifting the body’s hormonal response and helping muscles use glucose more effectively.
Diet also matters, but this is not about starving yourself or cutting out every carbohydrate. It is about choosing foods that lead to steadier blood sugar control.
Dietary recommendations
High-fiber foods
Fiber helps slow the rise in blood sugar after meals and can help you feel full longer.
Examples:vegetables
beans
lentils
berries
apples
pears
chia seeds
oats
whole grain breads
brown rice
quinoa
Low glycemic index foods
These foods tend to raise blood sugar more slowly and steadily.
Examples:plain Greek yogurt
beans and lentils
sweet potatoes
steel-cut or old-fashioned oats
apples
berries
non-starchy vegetables
chickpeas
whole grain pasta in reasonable portions
brown rice or quinoa
High-quality protein
Protein helps with satiety and can help blunt blood sugar spikes when paired with carbohydrates.
Examples:eggs
Greek yogurt
cottage cheese
chicken
turkey
fish low in mercury
lean beef
tofu
edamame
nuts
nut butters
cheese in reasonable portions
Hydration matters
Aim for around 80 ounces of water daily unless you have been given different instructions. Staying hydrated is important in pregnancy overall and can also help support healthier eating habits.Avoid sugary beverages
Liquid sugar can drive blood sugar up very quickly and is one of the easiest places to make meaningful changes.
Try to avoid:juice
regular soda
sweet tea
sweetened coffee drinks
sports drinks
energy drinks
flavored milk
chocolate milk
sugary smoothies
other sweetened beverages
A good rule of thumb is this: build meals around protein, fiber, and smarter carbohydrates, rather than eating large amounts of fast-absorbing carbs by themselves.
How are blood sugars followed?
Once treatment starts, blood sugar monitoring is used to make sure control has actually been achieved.
A common approach is to check:
a fasting blood sugar
blood sugars after meals
The usual goals are:
fasting values below 95
1-hour post-meal values below 140
2-hour post-meal values below 120
These numbers are often reviewed weekly, though sometimes more often if values are running high.
What if diet and exercise are not enough?
If blood sugars cannot be consistently controlled with nutrition changes and exercise, medication may be needed.
Insulin is the preferred medication when medication is required in pregnancy. There are situations where oral medications such as metformin are used, especially if a patient declines insulin, cannot safely administer it, or cannot afford it. Glyburide is generally not considered first-choice treatment.
Needing medication does not mean you failed. It means the placenta is creating more insulin resistance than your body can overcome on its own.
Does gestational diabetes change the pregnancy?
Sometimes, yes.
Patients with gestational diabetes may need:
closer follow-up
growth assessment later in pregnancy
fetal surveillance in some cases
delivery planning based on blood sugar control and the overall clinical picture
When should I call Calhoun Women’s Center?
Please call us if:
your blood sugar numbers are repeatedly above goal
you are not sure how or when to check your sugars
you are struggling to understand the food plan
you are having frequent low blood sugars
you are vomiting or unable to keep food down
you have been diagnosed and are not sure what happens next
You are not expected to sort this out by yourself.
When should I seek urgent care right away?
Please seek urgent evaluation if:
you cannot keep fluids down
you feel faint, confused, or severely weak
you are having significant symptoms that may be related to either low or high blood sugar
your blood sugar is generally below 70 or above 200
you have concerning pregnancy symptoms such as heavy bleeding, severe abdominal pain, decreased fetal movement, or symptoms concerning for preeclampsia
Symptoms of low and high blood sugar can sometimes feel very similar. If you are feeling significantly unwell, especially when your sugar is clearly too low or too high, you should seek care.
What about delivery timing?
This depends on how severe the gestational diabetes is and how well it is controlled.
In general:
patients with diet-controlled gestational diabetes are usually not delivered before 39 weeks unless there is another reason
patients with well-controlled gestational diabetes on medication are often delivered around 39 weeks
the exact plan depends on blood sugar control and the overall clinical picture
That does not mean every patient with gestational diabetes gets induced early. It means delivery planning is individualized based on the actual situation.
What about after delivery?
This part matters more than many patients realize.
Gestational diabetes often improves after delivery, but it is also a warning sign that your body may be at increased risk for future diabetes. Because of that, postpartum testing is recommended at 4–12 weeks postpartum. Continued screening every 1–3 years after that is also important, even if the first postpartum test is normal.
In other words: delivery is not the end of the story.
Final thoughts
A diagnosis of gestational diabetes can feel overwhelming at first, but this is something we manage all the time. Most patients do very well when it is recognized early, monitored carefully, and treated appropriately. The goal is not perfection. The goal is healthy blood sugars, thoughtful follow-up, and the safest pregnancy possible for both mom and baby.
Professional references
ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus
Additional patient education and clinical guidance adapted for Calhoun Women’s Center
