Medically Reviewed and Compiled by Dr. [Adam N. Khan], MD.
Quick summary (one line)
Gestational diabetes is high blood sugar first recognized during pregnancy; many people have no symptoms, so screening and prevention matter.
What gestational diabetes is
Gestational diabetes (GDM) is glucose intolerance that begins or is first detected during pregnancy. It usually resolves after delivery but raises the risk of complications during pregnancy and of type 2 diabetes later for the parent and child. Screening, diagnosis, and treatment reduce most short-term risks.
Symptoms to watch for
Most people with gestational diabetes have no symptoms and are diagnosed by routine testing. When symptoms occur they tend to be mild and include:
- Increased thirst and more frequent urination.
- Tiredness or fatigue that is worse than typical pregnancy fatigue.
- Blurred vision or dry mouth.
- Recurrent yeast infections (vaginal thrush).
If you notice these, mention them to your clinician, but absence of symptoms does not rule out GDM — that is why screening is standard.
Who is at higher risk
Common, evidence-backed risk factors:
- Prepregnancy overweight or obesity.
- Age over about 35 years.
- Prior gestational diabetes in an earlier pregnancy.
- Family history of type 2 diabetes.
- Certain racial and ethnic groups have higher prevalence (clinician will tailor screening).
These raise the chance GDM will develop, but anyone can get GDM. Because many cases are silent, universal or risk-based screening is recommended.
Screening and diagnosis (what to expect)
- Routine screening is typically performed between 24 and 28 weeks of pregnancy for average-risk people. High-risk people may have early testing.
- Two commonly used approaches: the one-step 75 g oral glucose tolerance test or the two-step method (50 g screening followed by 100 g OGTT if screening is positive). Different clinics may use different protocols.
If screening is abnormal, your provider will guide further testing and management. Early diagnosis improves monitoring and outcomes.
Short-term risks if GDM is untreated
- Larger babies (macrosomia) which increase chances of birth injury and cesarean delivery.
- Low blood sugar (hypoglycemia) in the newborn after delivery.
- Higher risk of pregnancy high blood pressure and preeclampsia.
Timely management (diet, glucose monitoring, and if needed medication) lowers these risks.
Prevention: practical, evidence-based steps
These measures reduce the risk of developing GDM or limit its severity when started before or during early pregnancy.
Before pregnancy (ideal window)
- Achieve a healthy weight. Even modest weight loss before conception reduces insulin resistance and GDM risk.
- Start regular moderate physical activity (target ~150 minutes per week). Exercise before pregnancy lowers later GDM risk.
- Eat a balanced diet — prioritize whole grains, vegetables, lean protein, and limit sugar-sweetened beverages. Reducing sugary drinks is linked to lower GDM risk in studies.
During pregnancy
- Early prenatal visit: review risk factors and test for undiagnosed type 2 diabetes if high risk.
- Follow recommended screening at 24–28 weeks (or earlier if high risk).
- Maintain or adopt regular moderate exercise (walks, prenatal-approved aerobic activity) totaling about 150 minutes weekly unless contraindicated. Exercise lowers GDM risk and helps glucose control.
- Nutrition support: medical nutrition therapy from a registered dietitian improves glucose control. Focus on portion control, timing of carbohydrates, and balanced meals.
- Limit sugar-sweetened beverages and excess weight gain during pregnancy.
After delivery (to reduce long-term risk)
- Postpartum glucose testing is recommended 4–12 weeks after birth to check whether glucose intolerance resolved. Continued surveillance every 1–3 years is common.
- Breastfeed when possible. Longer duration of lactation is associated with lower maternal risk of later type 2 diabetes.
- Maintain healthy weight and regular physical activity to reduce progression to type 2 diabetes.
How gestational diabetes is treated (brief)
First-line treatment is medical nutrition therapy and exercise with frequent blood glucose monitoring. If glucose targets are not met, medication (insulin is standard; some centers use certain oral agents) is added. The treatment goal is a safe glucose range to minimize risks to parent and baby.
Unique Clinical Takeaways
These are practical, clinician-focused insights that go beyond a simple symptom list.
1) Symptom silence does not equal low risk — rely on risk profile and timing
Because most patients do not have noticeable symptoms, relying on subjective symptoms misses many cases. A careful risk review at the first prenatal visit (prepregnancy BMI, past GDM, family history) plus routine testing at 24 to 28 weeks is the safer strategy. Do not delay testing when risk factors are present.
2) Early glucose abnormalities predict different trajectories — stratify follow-up
Patients with abnormal early pregnancy glucose tests (first trimester) represent a different phenotype: some have undiagnosed type 2 diabetes, others will develop classic late GDM. Those with early abnormalities need closer monitoring and may need earlier interventions. Treat them more like high-risk patients rather than waiting for the 24–28 week screen.
3) Social and behavioral factors change risk and outcomes — make prevention multidisciplinary
Access to healthy food, safe spaces for exercise, culturally appropriate nutrition counseling, and support for breastfeeding all change outcomes. Clinicians should identify social barriers early and connect patients to dietitians, community resources, and lactation support. This lowers both short-term obstetric complications and long-term diabetes risk. Population studies link sugary beverage intake and socioeconomic factors to higher GDM rates. Addressing these reduces incidence.
4) Postpartum care is part of pregnancy care — build it in before delivery
Many people with GDM do not complete recommended postpartum glucose testing. Scheduling the postpartum glucose test and providing patient education before discharge improves follow-up rates. Also, emphasize breastfeeding and weight management as preventive measures against type 2 diabetes.
When to call your clinician now
Call if you have:
- New, severe thirst or urination, sudden vision changes, or signs of infection.
- If you have known GDM and home glucose readings are frequently above your target range.
Practical patient checklist
- Attend first prenatal visit and review risk factors.
- Complete screening at 24–28 weeks (or earlier if high risk).
- Aim for ~150 minutes of moderate activity weekly unless contraindicated.
- Limit sugar-sweetened drinks and follow a balanced meal plan.
- Plan postpartum glucose testing and breastfeeding support.
References and Citations
(Authoritative sources used in this article)
- Centers for Disease Control and Prevention (CDC). Gestational Diabetes — overview and symptoms. CDC
- American College of Obstetricians and Gynecologists (ACOG). Practice Bulletin No. 190 and guidance on screening and exercise in pregnancy. LWW Journals+1
- Mayo Clinic. Gestational diabetes — symptoms, diagnosis, and treatment. mayoclinic.org+1
- World Health Organization (WHO). Diabetes fact sheet and gestational diabetes definitions. World Health Organization
- American Diabetes Association (ADA). Gestational diabetes information and breastfeeding guidance. American Diabetes Association+1
- Cleveland Clinic. Gestational diabetes overview and management. Cleveland Clinic
- StatPearls / NCBI Bookshelf. Gestational diabetes review and risk factors. NCBI
- Selected peer-reviewed studies and guideline reviews on risk factors, breastfeeding, and physical activity (Diabetes Care standards and lactation research). Diabetes Journals+1
Medical disclaimer
This article is for educational purposes only. It does not replace personalized medical advice from your clinician. If you are pregnant or planning pregnancy, talk to your healthcare provider about testing, prevention, and management tailored to your health and pregnancy. In emergencies or if you have severe symptoms, seek immediate medical attention.