Gestational diabetes is a form of diabetes that develops during pregnancy. Although it usually resolves once your baby is born, it can increase the risk of health problems for you and your baby.
Your body usually controls blood sugar through a hormone called insulin. However, as your body changes during pregnancy — including weight gain and hormonal changes — your body may become less sensitive to insulin. This is called insulin resistance.
Gestational diabetes usually develops between weeks 24 and 28 of pregnancy, and it’s often symptomless. This means that a doctor can usually only spot it after blood tests.
That’s why regular appointments and checkups are essential during pregnancy. Gestational diabetes is fairly common, too, affecting around 10% of pregnancies in the United States.
If you develop gestational diabetes, your risk of developing type 2 diabetes increases — around 50% of people who experience gestational diabetes develop type 2 diabetes later in life.
The exact cause of gestational diabetes is still unclear, but you may be able to manage the condition with exercise and a healthy diet. Treatment might also include regular blood sugar checks and insulin injections.
At ZOE, we run the largest nutrition science study of its kind. Our results show that the way people's blood sugar levels respond to food varies significantly between individuals.
Although our program isn't currently available for pregnant people, once you've given birth and can focus on yourself, we can provide you with personalized nutrition advice to help you eat the best foods for your body.
Signs and symptoms
Gestational diabetes rarely causes noticeable symptoms. If it does, they’re usually mild and include:
feeling more thirsty than usual
needing to pee more often
being particularly tired
Because symptoms are either subtle or absent, doctors run blood tests to check for gestational diabetes whether or not you have symptoms.
Causes and risk factors
Insulin helps sugar move from your blood into your cells. However, during pregnancy, your hormone levels change, leading to insulin resistance — meaning that your cells stop responding so well to insulin.
Insulin resistance means that your body needs to produce more insulin to keep blood sugar levels in check.
Insulin resistance happens during every pregnancy to different degrees.
Gestational diabetes risk factors
Although scientists don’t know why gestational diabetes develops in some people but not others, they do know some factors that make it more likely. These include:
having a family history of type 2 diabetes
having a diagnosis of gestational diabetes in an earlier pregnancy
having given birth to a child weighing 9 pounds or more
having overweight or obesity
being over 25 years of age
having polycystic ovary syndrome (PCOS)
Also, people who are African American, Hispanic/Latino, Native American, Alaska Native, Native Hawaiian, or Pacific Islander have an increased risk.
How to reduce your risk of gestational diabetes
During pregnancy, by eating a healthy diet and exercising regularly, it’s possible to reduce the risk of gestational diabetes.
If you have overweight or obesity, losing weight before getting pregnant can reduce the risk, too.
When you exercise, your muscles take in sugar, which means there is less in your blood. Even when you finish exercising, your muscles remain more sensitive to insulin, helping to keep blood sugar levels in check.
The Centers for Disease Control and Prevention (CDC) suggest:
“Pregnant or postpartum women should do at least 150 minutes (for example, 30 minutes a day, 5 days a week) of moderate-intensity aerobic physical activity per week, such as brisk walking, during and after their pregnancy. It is best to spread this activity throughout the week.”
Gestational diabetes increases the risk of health problems for you and your baby. Below, we will outline some of these risks.
Complications if you’re pregnant
Gestational diabetes increases the risk of:
Developing pre-eclampsia: A serious condition that causes high blood pressure.
Having a C-section: Excess blood sugar can boost your baby's growth. A larger baby is more likely to require a C-section or surgical delivery.
Developing type 2 diabetes: After recovering from gestational diabetes, your risk of type 2 diabetes increases. This is a serious, life-long condition where blood sugar levels remain high.
At ZOE, we run the largest ongoing scientific study of nutrition. We have shown that blood sugar and insulin responses following a meal can vary between people. Once your baby is born, our at-home test can help you understand how food affects your blood sugar levels. Save this link to our free quiz.
Complications for baby
Gestational diabetes not only puts your body at risk, but also it can affect the health of your baby. Too much glucose in your bloodstream means that the baby also has high glucose in their blood since glucose can cross the placenta to reach the baby.
This extra glucose means there is more energy than needed, and this extra energy is stored in the baby’s body as fat, which can cause serious health problems, including:
a larger birth weight, which increases the risk of problems during delivery for both mother and baby
low blood sugar at birth; this happens because your baby’s pancreas has to produce extra insulin
an increased risk of obesity and type 2 diabetes later in life
stillbirth or miscarriage, but this is rare and more common in people who already have diabetes before pregnancy
Join our mailing list
Sign up for fresh insights into our scientific discoveries and the latest nutrition updates. No spam, just science.
When to see a doctor
Those who are pregnant should have regular checkups with a doctor. These appointments may include a glucose tolerance test.
People who have a high risk of gestational diabetes will likely need to see the doctor more often, including those who have type 2 diabetes, overweight, or obesity before pregnancy.
If the doctor diagnoses gestational diabetes, they’ll recommend how to manage your diet and put an exercise plan in place to help you control your blood sugar. They may also prescribe a course of insulin shots and recommend regular blood sugar testing.
Gestational diabetes can develop when your body becomes less able to control your blood sugar during pregnancy. It’s often symptomless, and doctors aren’t sure what causes it.
This condition generally gets better once your baby meets the world, but it can increase your risk of pre-eclampsia, type 2 diabetes later in life, and birth complications.
Eating food that works best for your body and keeping up with a regular exercise routine can help you reduce your risk of gestational diabetes during pregnancy.
If you’d like to understand more about blood sugar, read this article on blood sugar after eating.
Definition & facts of gestational diabetes. (2017). https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/gestational/definition-facts
Diabetes risk factors. (2022). https://www.cdc.gov/diabetes/basics/risk-factors.html
Exercising with gestational diabetes. (n.d.). https://www.diabetes.co.uk/gestational-diabetes/exercising-with-gestational-diabetes.html
Gestational diabetes. (n.d.). https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/gestational
Gestational diabetes and a healthy baby? Yes. (n.d.). https://www.diabetes.org/diabetes/gestational-diabetes
Healthy pregnant or postpartum women. (2021) https://www.cdc.gov/physicalactivity/basics/pregnancy/index.htm
How gestational diabetes can impact your baby? (n.d.). https://www.cdc.gov/pregnancy/diabetes-gestational.html
Pre-eclampsia and diabetes. Current Diabetes Reports. (2015). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4317712/
Treatment & perspective. (n.d.). https://www.diabetes.org/diabetes/gestational-diabetes/how-to-treat-gestational-diabetes