Gestational diabetes mellitus (GDM) is a form of high blood sugar that develops during pregnancy and typically resolves after delivery. It’s one of the more commonly discussed pregnancy complications associated with advanced maternal age, and understanding its risk factors, screening process, and management approach can help you engage more confidently with your prenatal care team.
It’s worth noting upfront that gestational diabetes is manageable. Many women diagnosed with GDM have healthy pregnancies and healthy babies, particularly when the condition is identified early and monitored appropriately. A diagnosis of GDM is not a reason for alarm, but it is a reason to work closely with your healthcare team throughout the remainder of your pregnancy.
How Gestational Diabetes Develops and Why Age Is a Factor
During pregnancy, the placenta produces hormones that can interfere with the body’s ability to use insulin effectively — a phenomenon called insulin resistance. For most pregnant women, the pancreas compensates by producing more insulin. In women who develop GDM, this compensation is insufficient, and blood glucose levels rise beyond normal pregnancy ranges.
Age is one of several risk factors associated with increased GDM likelihood. According to the Centers for Disease Control and Prevention, women over 35 have a higher risk of gestational diabetes compared to younger pregnant women. Research suggests that metabolic changes associated with aging — including modest increases in insulin resistance and changes in pancreatic beta cell function — may contribute to this elevated risk, though age is one factor among several.
Additional risk factors for gestational diabetes include pre-pregnancy BMI above normal range, family history of type 2 diabetes, previous pregnancy affected by GDM, PCOS, certain ethnic backgrounds with higher baseline prevalence, and carrying multiples.
Screening: What to Expect and When
Gestational diabetes screening is recommended for all pregnant women and is typically conducted between 24 and 28 weeks of pregnancy — though women with higher risk factors may be screened earlier, sometimes in the first trimester.
The Glucose Challenge Test (GCT)
The initial screening is usually the one-hour glucose challenge test (GCT), sometimes called the glucose screen. You drink a sweet glucose solution and have a blood draw one hour later. This test does not require fasting beforehand. If blood glucose exceeds the threshold (typically around 130–140 mg/dL, depending on the lab), a follow-up diagnostic test is ordered.
The Oral Glucose Tolerance Test (OGTT)
If the GCT result is above threshold, the diagnostic test — the three-hour oral glucose tolerance test (OGTT) — is performed. This test requires an overnight fast, and blood draws are taken at fasting, one hour, two hours, and three hours after drinking a larger glucose solution. GDM is typically diagnosed if two or more of these values exceed established thresholds.
It’s worth noting that an elevated GCT result does not mean you have gestational diabetes — many women who exceed the initial screening threshold have normal OGTT results. The two-step process is designed to avoid over-diagnosis based on a single elevated measurement.
Managing Gestational Diabetes During Pregnancy
For most women with GDM, initial management involves dietary changes and regular blood glucose monitoring. A registered dietitian with experience in gestational diabetes can help develop an eating pattern that supports blood glucose control while meeting the nutritional needs of pregnancy. Common approaches include distributing carbohydrates across meals and snacks, choosing lower-glycemic carbohydrate sources, and pairing carbohydrates with protein and healthy fats.
Regular physical activity, as advised by your healthcare provider based on your individual pregnancy, may also support blood glucose management. For many women, these lifestyle approaches are sufficient to keep blood glucose within target ranges throughout pregnancy.
If dietary changes and activity are insufficient to reach target glucose levels, medication may be recommended. Insulin is the most commonly used medication for GDM in the US and has a long safety record in pregnancy. Oral medications such as metformin are used in some settings, though practices vary.
Monitoring and Prenatal Care Considerations
Women diagnosed with gestational diabetes typically have additional monitoring during the remainder of pregnancy. This may include more frequent prenatal appointments, additional ultrasounds to monitor fetal growth (as GDM can be associated with larger-than-average birth size, called macrosomia), and non-stress tests in the third trimester depending on how well blood glucose is controlled.
Your OB/GYN or midwife will guide the frequency and type of additional monitoring based on your individual glucose control and other pregnancy factors. Working closely with your prenatal team and following your personalized prenatal care plan provides the best support for both you and your baby.
After Delivery: Follow-Up and Long-Term Health
Gestational diabetes typically resolves after delivery, and most women return to normal blood glucose levels relatively quickly. However, GDM is associated with a longer-term increase in the risk of developing type 2 diabetes — research suggests that women with a history of GDM have a significantly higher lifetime risk compared to those without this history.
For this reason, postpartum follow-up glucose testing is recommended, typically with a 75-gram OGTT at 4–12 weeks after delivery. Longer-term, annual screening for blood glucose is often recommended. Lifestyle approaches — including regular physical activity and a diet that supports metabolic health — are associated with reducing the risk of progression to type 2 diabetes, according to research from the NIH.
This doesn’t mean GDM is a harbinger of inevitable future health problems — it’s an opportunity for awareness and proactive health monitoring. Learning more about postpartum health after 35 can help you think about the longer view of your wellbeing after delivery.
Frequently Asked Questions
Does gestational diabetes mean I’ll have type 2 diabetes later?
A history of gestational diabetes does increase the long-term risk of type 2 diabetes, but it does not guarantee it. Research suggests that lifestyle factors — particularly regular physical activity and a diet that supports metabolic health — may reduce this risk significantly. Regular screening after pregnancy helps catch any blood sugar changes early, when they’re most manageable.
Is gestational diabetes my fault?
No. Gestational diabetes results from a combination of hormonal and metabolic factors inherent to pregnancy, overlaid on individual genetic and health factors. While certain modifiable factors can influence risk, many women with healthy pregnancies and lifestyles develop GDM due to factors outside their control. Managing it proactively, rather than dwelling on its origin, is the most constructive approach.
Will my baby have diabetes if I have gestational diabetes?
Babies born to mothers with GDM are not born with diabetes. However, they may be at slightly higher long-term risk of obesity and type 2 diabetes compared to the general population, according to some research. Breastfeeding, if possible, and supporting healthy lifestyle habits in childhood are factors that research associates with reducing this risk.
Do I need a C-section if I have gestational diabetes?
Not necessarily. Many women with well-controlled gestational diabetes deliver vaginally. The mode of delivery depends on many factors, including fetal size, blood glucose control during pregnancy, and other individual clinical considerations. This is best discussed with your OB/GYN based on your specific pregnancy.
Key Takeaways
- Gestational diabetes is more common in women over 35 but is manageable with appropriate care; many women with GDM have healthy pregnancies and babies.
- Standard screening involves a two-step process (glucose challenge test followed by oral glucose tolerance test if needed) between 24–28 weeks.
- Initial management typically focuses on dietary adjustments and blood glucose monitoring; insulin or oral medication may be recommended if needed.
- Women with GDM receive additional monitoring during pregnancy, including growth ultrasounds and potentially non-stress tests.
- Postpartum follow-up testing is important, as GDM is associated with an increased long-term risk of type 2 diabetes that can be reduced through proactive health monitoring and lifestyle choices.
This content is for informational purposes only and does not constitute medical advice. Individual health situations vary significantly. Always consult a qualified healthcare provider before making decisions related to your health, fertility, or pregnancy.
About the Author
Emily Carter is a women’s health writer focused on fertility, pregnancy after 35, and sleep changes in midlife. She writes research-informed, non-alarmist content to help women navigate reproductive and hormonal transitions with clarity and confidence.