Gestational Diabetes: What to Know During and After Pregnancy

A pregnant woman holding a paper heart in front of her belly — Photo: Pixabay via Wikimedia Commons (CC0). Image credits

Last reviewed: October 9, 2026 · Sources: CDC, NIH/NIDDK, American Diabetes Association

Gestational diabetes is diabetes that develops during pregnancy in someone who did not have diabetes before. It is usually found through routine testing, often has no symptoms, and in most cases goes away after the baby is born. With good care, most people with gestational diabetes have healthy pregnancies and healthy babies. This guide explains what gestational diabetes is, who is at risk, how it is tested and treated, and what to do after delivery. It is not a substitute for advice from your obstetric and diabetes care team.

What causes gestational diabetes?

During pregnancy, the placenta makes hormones that help the baby grow. Some of these hormones make the body's cells more resistant to insulin. Most pregnant people's bodies respond by making more insulin. When the pancreas cannot make enough extra insulin to overcome this resistance, blood glucose rises, resulting in gestational diabetes. According to NIDDK, hormonal changes and extra weight during pregnancy contribute, and gestational diabetes is not caused by anything the pregnant person did wrong.

Who is at risk?

Gestational diabetes can happen to anyone during pregnancy, but certain factors raise the risk. Commonly cited risk factors include:

Having overweight or obesity before pregnancy
Having had gestational diabetes in a previous pregnancy
Having previously given birth to a baby weighing more than 9 pounds
Having prediabetes
Having a parent or sibling with type 2 diabetes
Having polycystic ovary syndrome (PCOS)
Being physically inactive
Being older at the time of pregnancy

Some racial and ethnic groups, including African American, Hispanic/Latino, American Indian, Alaska Native, Asian American, and Pacific Islander people, are at higher risk.

Symptoms

The CDC notes that gestational diabetes usually does not have any symptoms. Increased thirst and urination are common in pregnancy anyway, so symptoms are not a reliable guide. That is why routine testing matters.

Testing

The CDC advises that pregnant people be tested for gestational diabetes between 24 and 28 weeks of pregnancy. People with risk factors may be tested earlier in pregnancy to check for diabetes that existed before pregnancy but was not diagnosed.

Testing is done with an oral glucose tolerance test. There are two common approaches:

Two-step approach: A one-hour glucose challenge test after drinking a sugary solution, without fasting. If the result is high, a longer, fasting glucose tolerance test follows.
One-step approach: A fasting two-hour glucose tolerance test after drinking a sugary solution, with blood drawn several times.

Your provider will explain which test is used and what the results mean. The American Diabetes Association also has more information on testing.

Why it matters for the baby

When the parent's blood glucose is high, extra glucose crosses the placenta. The baby's pancreas makes extra insulin in response, and the baby may grow larger than usual. NIDDK and the ADA describe possible effects, including:

A larger baby (sometimes called macrosomia), which can make delivery more difficult and increase the chance of a cesarean birth
Early (preterm) birth
Breathing problems in the newborn
Low blood glucose in the baby shortly after birth
A higher chance for the child of developing obesity and type 2 diabetes later in life

Why it matters for the parent

Gestational diabetes can increase the chance of high blood pressure and preeclampsia during pregnancy and of needing a cesarean delivery. After pregnancy, the CDC notes that gestational diabetes raises the risk of developing type 2 diabetes later in life.

Treatment

The goal of treatment is to keep blood glucose in a target range set by your care team. Treatment usually involves:

Checking blood glucose

Most people with gestational diabetes check their blood glucose several times a day, often fasting in the morning and after meals. Your care team will give you specific targets and tell you how often to check. See checking blood sugar and CGMs.

Healthy eating

A registered dietitian or diabetes educator can help create a meal plan that supports the baby's growth while managing glucose. Plans often spread carbohydrates across three meals and several snacks, focus on high-fiber carbohydrates, pair carbs with protein, and limit sugary drinks and sweets. Learning to count carbohydrates may be part of the plan. Pregnancy is not a time for restrictive dieting; follow your care team's guidance.

Physical activity

If your provider says it is safe, regular moderate activity such as walking can help lower blood glucose. Many people find a short walk after meals helpful.

Medicine when needed

The CDC notes that if healthy eating and activity are not enough, your doctor may prescribe medicine. Insulin is commonly used because it is effective and does not cross the placenta in significant amounts. Some providers may use certain oral medicines in some situations. See our insulin basics guide.

Extra monitoring

Your care team may recommend additional prenatal visits, ultrasounds to check the baby's growth, and tests of the baby's well-being later in pregnancy.

Labor and delivery

Most people with well-managed gestational diabetes can plan for a vaginal birth. Your team will monitor your glucose during labor, especially if you have been using insulin. After birth, the baby's blood glucose will be checked, and early feeding helps keep the baby's glucose stable.

After the baby is born

Gestational diabetes usually goes away after delivery, but follow-up is important:

Postpartum glucose test: The ADA recommends testing for diabetes or prediabetes at 4 to 12 weeks after delivery, often with an oral glucose tolerance test.
Lifelong screening: Because of the increased risk of type 2 diabetes, people who have had gestational diabetes should be tested for diabetes or prediabetes regularly, generally at least every three years, or as their provider advises.
Breastfeeding: Breastfeeding provides many benefits and may help lower the parent's risk of later type 2 diabetes.
Future pregnancies: Gestational diabetes may return in a later pregnancy. Planning ahead and getting tested early is helpful.

Lowering your future risk

After gestational diabetes, the same steps that prevent type 2 diabetes apply: reaching or maintaining a healthy weight, regular physical activity, and healthy eating. The CDC states that people with prediabetes can lower their risk of type 2 diabetes through modest weight loss and regular activity, and the National Diabetes Prevention Program is a structured option. See our prediabetes guide and type 2 diabetes overview.

Can gestational diabetes be prevented?

The CDC notes that if you are at risk, you may be able to prevent gestational diabetes with lifestyle changes, including healthy eating and regular physical activity before and during pregnancy. Reaching a healthier weight before pregnancy, if you have overweight, may also help. Not every case can be prevented.

Emotional health

A gestational diabetes diagnosis can feel stressful, especially when you are already adjusting to pregnancy. It is normal to feel worried. Remember that gestational diabetes is common, treatable, and not your fault. Ask your care team questions and lean on support from family, friends, and educators.

Key takeaways

Gestational diabetes develops during pregnancy due to hormone-related insulin resistance.
It usually has no symptoms, so testing between 24 and 28 weeks is recommended.
Treatment includes glucose monitoring, healthy eating, activity, and medicine such as insulin when needed.
It usually resolves after birth, but it raises the future risk of type 2 diabetes, so follow-up testing is important.

Sources

Links to the sources cited above appear in the text. We rely on the Centers for Disease Control and Prevention (CDC), the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), and the American Diabetes Association (ADA).

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