Gestational diabetes is high blood glucose that develops during pregnancy, usually in the second or third trimester. It occurs when pregnancy-related hormonal changes increase insulin resistance, and the body cannot produce enough insulin to meet the increased demand.
In 2024, an estimated 23.3 million live births (15.6%), had some form of high blood glucose (hyperglycaemia) during pregnancy. The condition is more common in low- and middle-income countries with limited access to maternal care.
Understanding gestational diabetes
Most people with gestational diabetes do not experience noticeable symptoms and are diagnosed through routine pregnancy screening. Although the condition often resolves after birth, it can affect both maternal and foetal health if not managed properly.
Gestational diabetes can affect the health of the mother and the baby, with possible long-term consequences. It can lead to pregnancy-related complications, including high blood pressure, large birth weight babies and obstructed labour. It also increases the likelihood of developing type 2 diabetes later in life for both mother and child.
Lifestyle changes and medication can help manage the condition. With the right support, including healthy nutrition, physical activity, monitoring and medical care, gestational diabetes can be managed effectively.
What is gestational diabetes?
Gestational diabetes mellitus (GDM) is a type of diabetes that develops during pregnancy. The placenta produces hormones that can interfere with the body’s ability to use insulin effectively. This is known as insulin resistance, a normal part of pregnancy. However, in some women, insulin resistance becomes too high, leading to gestational diabetes.
During pregnancy, the placenta produces hormones that help the baby grow and develop. However, these hormones can also interfere with how insulin works, leading to insulin resistance. When the body cannot produce enough insulin to compensate, blood glucose levels rise, and gestational diabetes develops.
Gestational diabetes usually develops in the second or third trimester of pregnancy and often resolves after birth. However, women who experience gestational diabetes are at greater risk of developing type 2 diabetes later in life. Furthermore, children whose mother had gestational diabetes are at increased risk of type 2 diabetes later in life. They also have a higher risk of overweight/obesity, which itself increases type 2 diabetes risk.
Many women with gestational diabetes experience no symptoms, which is why routine screening during pregnancy is important.
What makes gestational diabetes different?
Gestational diabetes has unique characteristics that set it apart from other types of diabetes.
Key differences include:
- Develops specifically during pregnancy
- Usually resolves after childbirth
- Linked to hormonal changes produced by the placenta
- Can affect both mother and baby
- Strongly associated with future type 2 diabetes risk
- Often diagnosed through routine screening rather than symptoms
- Usually temporary, but long-term health monitoring remains important
Global impact of gestational diabetes
Gestational diabetes is becoming more common worldwide, particularly in low- and middle-income countries where access to maternal healthcare may be limited.
In 2024, an estimated 23.3 million live births – 1 in 5 – were affected by hyperglycaemia during pregnancy.
The growing prevalence of gestational diabetes reflects wider increases in obesity, sedentary lifestyles and type 2 diabetes globally. Improving maternal healthcare, screening access and prevention programmes is essential to reducing the long-term impact on women, children and healthcare systems worldwide.
Why gestational diabetes matters
Gestational diabetes is not just a short-term condition during pregnancy. It can have important health implications for both the mother and baby during pregnancy and beyond.
Without appropriate management, gestational diabetes can increase the risk of:
- High blood pressure during pregnancy
- Pre-eclampsia
- Difficult labour and delivery complications
- Caesarean birth
- Large birth weight babies (macrosomia)
- Premature birth
- Future type 2 diabetes for the mother
- Overweight or obesity and type 2 diabetes later in life for the child
Early diagnosis and proper support can help reduce these risks and improve outcomes for both mother and baby.
Effects of gestational diabetes on the baby
Gestational diabetes can affect the baby both during pregnancy and after birth. Risks vary depending on blood glucose management and overall pregnancy health.
Possible effects on the baby include:
- Higher birth weight (macrosomia)
- Premature birth
- Breathing difficulties after birth
- Low blood glucose levels shortly after delivery
- Increased risk of overweight or obesity later in life
- Increased likelihood of developing type 2 diabetes in adulthood
Careful monitoring and management during pregnancy can significantly reduce these risks.
Who is at risk of gestational diabetes?
The exact cause of gestational diabetes (GDM) is not yet known. However, several risk factors can increase the chances of developing GDM.
These include:
- Overweight or obesity
- Being over the age of 45
- Family history of diabetes
- Previous gestational diabetes
- Previous pregnancy involving a large birth weight baby
- Polyendocrine Metabolic Ovarian Syndrome (PMOS), previously polycystic ovary syndrome (PCOS)
- Unbalanced or inadequate nutrition before or during pregnancy
Women with one or more risk factors may benefit from earlier or additional screening during pregnancy.
Symptoms of gestational diabetes
Gestational diabetes often has no symptoms. However, some women may experience symptoms such as:
- Increased thirst
- Frequent urination
- Fatigue
- Blurred vision
- Nausea
- Frequent infections, such as yeast infections
Screening and diagnosis
Gestational diabetes is usually identified through routine screening during pregnancy.
Screening often takes place between the 24th and 28th weeks of pregnancy, although women at higher risk may be tested earlier.
Routine pregnancy screening
Many healthcare systems recommend routine testing for gestational diabetes during pregnancy because symptoms may not be obvious.
Early detection allows treatment to begin quickly, reducing the risk of complications for both mother and baby.
Glucose tolerance testing
The most common test used to diagnose gestational diabetes is the oral glucose tolerance test (OGTT).
This test measures how the body processes glucose after consuming a sugary drink. Blood glucose levels are checked before and after drinking the glucose solution.
Why early diagnosis matters
Identifying gestational diabetes early allows healthcare professionals to provide support with:
- Healthy nutrition
- Physical activity
- Blood glucose monitoring
- Medication when required
Timely intervention can improve pregnancy outcomes and reduce long-term health risks.
Managing gestational diabetes
Gestational diabetes can be managed with a combination of lifestyle changes and medication. In most cases, women with gestational diabetes can manage their blood glucose levels by making dietary changes and exercising regularly. However, some women may need insulin or other medications to control their glucose levels during pregnancy. For most women with GDM, glucose levels return to normal after delivery and treatment is no longer necessary.
Healthy nutrition during pregnancy
Nutrition plays a crucial role in managing gestational diabetes. Generally, women with gestational diabetes should eat a diet rich in vegetables, whole grains, lean proteins and healthy fats. In addition, smaller, more frequent meals throughout the day can help regulate blood sugar levels.
While there is no universal medical consensus on the nutritional components of a diet for women with GDM, healthy nutritional recommendations should consider carbohydrate portion size to limit glucose spikes. Carbohydrates include whole grains, such as bread, cereal, pasta and rice, and starchy vegetables, such as corn and peas. Always consult your healthcare professional to develop a suitable meal plan adjusted to your specific health requirements.
In addition to carbohydrates, nutritional meals should include plenty of whole fruits and vegetables and moderate amounts of lean proteins and healthy fats. It is best to avoid sugary foods and beverages, such as sodas, fruit juices and pastries.
Physical activity and pregnancy
Regular physical activity is another factor that can contribute to better glycaemic control. Any movement or exercise can help regulate glucose levels in women with GDM. It can also prevent excessive weight gain and reduce the risk of complications during pregnancy.
Healthcare professionals generally recommend moderate-intensity exercise for at least 30 minutes a day, most days. The best exercise options for pregnant women with GDM are low-intensity exercises such as walking, swimming, stationary cycling and prenatal yoga. Always consult your healthcare provider before starting any type of physical activity when pregnant.
Blood glucose monitoring
Women with gestational diabetes may need to monitor their blood glucose levels regularly during pregnancy.
Monitoring helps healthcare teams assess whether lifestyle changes are effective and whether additional treatment may be needed.
Medication and insulin treatment
Some women may require medication or insulin therapy if blood glucose levels cannot be managed through lifestyle measures alone.
Treatment decisions depend on individual needs and pregnancy health.
Long-term health risks from gestational diabetes
Although gestational diabetes usually resolves after childbirth, it can increase long-term health risks for both mother and child.
Risks for the mother
Women who have had gestational diabetes are at significantly higher risk of developing:
- Type 2 diabetes
- Gestational diabetes in future pregnancies
- Cardiovascular disease
Regular health monitoring after pregnancy is important.
Risks for the child
Children exposed to high blood glucose during pregnancy may have increased risk of:
- Childhood obesity
- Type 2 diabetes later in life
- Metabolic health problems
Supporting healthy family lifestyles after pregnancy can help reduce these risks.
Reducing the risk of gestational diabetes
Gestational diabetes cannot always be prevented, but healthy lifestyle habits before and during pregnancy may help reduce risk.
Prevention strategies include:
- Maintaining a healthy body weight
- Staying physically active
- Eating a balanced diet
- Managing existing health conditions
- Attending routine prenatal care appointments
Early detection of gestational diabetes is crucial for prompt treatment, which can help prevent complications for both mother and baby. Women at high risk of gestational diabetes should be screened during their first prenatal visit. Further recommendations advise screening all pregnant women for gestational diabetes between 24 and 28 weeks.
GDM resources
Guideline
IDF GDM Model of Care Implementation Protocol
The IDF GDM Model of Care was piloted in seven (urban and rural) collaborating health centres in Tamil Nadu State (South India), from June 2012 to December 2015. It was developed using best practice of care and established clinical guidelines.
GDM model of care implementation protocol
pdf
1MB
Guideline
Management of gestational diabetes in the community
A training manual for community health workers, developed as part of the IDF Women in India with GDM Strategy (WINGS).
Management of GDM in the community
pdf
1,017KB
Guideline
Having a baby? Now is the time to learn more about gestational diabetes
An educational manual with information and advice on having a healthy baby.
Learn more about GDM
pdf
1MB
