Gestational Diabetes: Causes, Risks, and Treatment

Have you been diagnosed with gestational diabetes? Perhaps you know someone who has it and would like to learn more. Or maybe you just want to educate yourself about the possible complications to watch out for in pregnancy. In any case, we’ve got you covered. Let’s learn about gestational diabetes.

Estimated reading time: 8 minutes

What is Diabetes?

Let’s start with an overview of diabetes mellitus, commonly known as diabetes, and what happens in a body that has diabetes. Your body takes the food you eat and breaks down the sugars and starches into glucose, which your body uses for energy. To help break down the sugar and allow your cells to use it, your pancreas produces a hormone called insulin. When your body is working properly, it produces just the right amount of insulin to keep the sugar in your blood at the right level (1).

In a person with diabetes, there is a problem with the way the body regulates glucose (sugar). There are two types of diabetes that non-pregnant people can develop. When a person has type 1 diabetes, their pancreas doesn’t make any insulin. In type 2 diabetes, the body doesn’t properly use the insulin that it makes, and later in the disease the body may not make enough insulin. Either way, the result is that there’s too much sugar in the blood (2).

Gestational Diabetes

Gestational diabetes mellitus, also called GDM or gestational diabetes, is when a woman who didn’t already have diabetes develops it during pregnancy. This happens in about 10% of pregnancies (3). The cause may be linked to a pregnancy hormone, human placental lactogen (HPL), which reduces insulin’s effect. In theory, this allows more glucose to support the growth of the baby (2). But in the case of gestational diabetes, the hormone changes alter the action of insulin too much and the body isn’t able to make enough insulin to offset the sugar. This causes high blood glucose, also called hyperglycemia.

Who Is At Risk?

Anyone can develop gestational diabetes. This is why screening is part of prenatal care for all pregnant women. However, some women have a higher chance of developing it than others. You may be more likely to develop GDM if you:

  • Are overweight or obese
  • Had gestational diabetes in a previous pregnancy (there is a 90% chance of having it in subsequent pregnancies)
  • Previously had a large baby who weighed nine pounds or more at birth
  • Have high blood pressure
  • Have heart disease
  • Are physically inactive
  • Have polycystic ovary syndrome
  • Have a parent or sibling with diabetes (1, 4)

How Serious Is It?

While diabetes may have once been a serious concern, today most women with gestational diabetes have healthy pregnancies and babies. Doctors know to screen during pregnancy and are better able to monitor sugar levels and treat the problem with diet and/or insulin. They also have more accurate ways to monitor the health of the baby. Still, it is important to carefully manage your gestational diabetes, as untreated diabetes can cause complications.

Risks for Mom

The maternal risks of gestational diabetes include:

  • High blood pressure, which is more common in GDM pregnancies
  • Pre-eclampsia, which is also more common if you have GDM
  • Increased chance of cesarean delivery due to concerns about baby’s size
  • Delivery of large a baby increases the chances of severe tears in the vagina or perineum, as well as heavy bleeding after delivery (1)

Risks for Baby

The risks of gestational diabetes for your baby include:

  • Macrosomia, which is a large baby, weighing more than 8 pounds 13 ounces
  • Very large babies stand a higher chance of injury during delivery, though most can be safely born vaginally
  • Increased risk of breathing problems after birth
  • Higher chance of jaundice after birth
  • May be born with low blood sugar (hypoglycemia)
  • Higher chance of obesity and diabetes later in life
  • Increased risk of stillbirth (1)

How is Gestational Diabetes Diagnosed?

In the United States, all pregnant women are screened for gestational diabetes in the second trimester between weeks 24 and 28 of pregnancy. (If your healthcare provider thinks you’re at risk for GDM, you may have the test earlier.) You’ll have a glucose challenge screening which involves drinking a sugary drink, waiting an hour, and then having a blood sample taken. This tests how well your body processes all the sugar you just drank.

If your blood glucose level is above a certain number, you’ll need to do a second test — the glucose tolerance test. This is a more involved three-hour test where your blood will be drawn every hour, watching for blood glucose levels to be below certain numbers at each draw.


One of the reasons that every pregnant woman is screened for gestational diabetes is because there are often no symptoms to alert you or your doctor to a problem. With any type of diabetes, there is sometimes an increase in thirst or urination, and sometimes a feeling of fatigue. However, these are hard to distinguish from normal pregnancy symptoms. Noticing that you are tired or visit the bathroom frequently may not sound at all unusual when you’re pregnant. But if symptoms seem excessive, mention to them to your provider. He or she may decide to screen you earlier, especially if you have any risk factors.

Gestational Diabetes Treatment

If you have gestational diabetes, treatments are aimed at keeping your blood sugar levels stable. Your doctor will first develop a plan with you to modify your diet and increase your activity level. (You may see a dietician to help you with this.) For many women, diet and moderate exercise alone are enough to control glucose levels. But if your levels are still too high, your doctor may prescribe insulin to manage your condition.

Your doctor will teach you how to monitor your glucose levels at home. This involves finger sticks to get a tiny drop of blood to be read by a glucose meter. It may sound scary or intimidating, but there is minimal discomfort and the meters are easy to use. You may keep track of your readings in a log book, but these days most monitors keep a digital record.

Additional Monitoring

In addition to helping you control your glucose levels through diet and/or insulin, your doctor will also want to keep a closer eye on your baby than if you didn’t have gestational diabetes. You will likely have prenatal appointments more often. Some of these appointments may include a nonstress test to check baby’s heart rate. Or, you may have a biophysical profile, which is a nonstress test plus an ultrasound to check on your little one (1). Your doctor may also ask you to do kick counts, or fetal movement counts, at home.


You may have heard that women with gestational diabetes can’t always have a vaginal delivery, and worry about how it affects your chances. While it is true that GDM can make your baby larger than normal, the good news is that most women with controlled gestational diabetes can have a vaginal delivery (4).

It’s likely that your doctor will talk to you about the benefits versus risks of delivering your baby early through a labor induction. And if your doctor thinks there’s good reason to believe that your baby is very large, he or she may discuss the benefits and risks of a cesarean delivery. If either of these situations arise, remember that you can and should ask as many questions as you need to, ask for a second opinion if you desire, and educate yourself about the possibilities.

After a Gestational Diabetes Pregnancy

Nearly all women see a return to normal blood glucose levels after their baby is born (5). However, know that half of all women who have had gestational diabetes will go on to develop type 2 diabetes later in life (6). For this reason, it is important that you are tested 6 – 12 weeks after your baby is born, and then every 1 – 3 years after that.

If you had gestational diabetes, your child may also be at a higher risk for developing diabetes and for being overweight (4). Tell your child’s doctor about your gestational diabetes so that he or she knows to monitor your child appropriately.

As you go forward, the best thing you can do to reduce the chance of developing type 2 diabetes (as well as other health problems) is to reach and maintain a healthy weight, make healthy dietary choices, and exercise regularly. Maintaining this healthy lifestyle for yourself and your child will also decrease his or her risk of developing diabetes or other health complications.

Kopa Birth’s online birthing classes allow you to prepare for a natural hospital birth from the comfort of your own home, 24/7. Enroll today in our free online childbirth class and start preparing for your natural birth!


  1. Gestational diabetes. (n.d.).
  2. Simkin, P., Whalley, J., Keppler, A., Durham, J., & Bolding, A. (2016). Pregnancy, Childbirth, and the Newborn: The Complete Guide. Minnetonka: Meadowbrook Press.
  3. Gestational diabetes. (n.d.).
  4. Gestational diabetes. (n.d.).
  5. Glade, B.C., Schuler, J.  (2011).  Your Pregnancy Week by Week, 7th edition.  First Da Capo Press
  6. Gestational diabetes and pregnancy. (2020, July 14).

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Meet Katie Griffin

I’m a registered nurse, Lamaze certified childbirth educator, and the mother of 7. I help women realize their dream of a natural, intimate, and empowering hospital birth.

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Have you been diagnosed with gestational diabetes? Perhaps you know someone who has it and would like to learn more. Or maybe you just want to educate yourself about the