The OGTT Screening Test
| Time | Normal | Gestational Diabetes |
|---|---|---|
| Fasting | <5.6 mmol/L | ≥5.6 mmol/L |
| 2 hours after glucose drink | <7.8 mmol/L | ≥7.8 mmol/L |
Who Is Screened Early (Risk Factors)
- BMI above 30
- Previous baby weighing 4.5kg or more
- Previous gestational diabetes
- Family history of diabetes (first-degree relative)
- Family origin with higher prevalence of diabetes (South Asian, Black, Middle Eastern)
Blood Glucose Targets During Pregnancy
| Time | Target |
|---|---|
| Fasting | <5.3 mmol/L |
| 1 hour after meals | <7.8 mmol/L |
| 2 hours after meals | <6.4 mmol/L |
Management
| Step | Approach |
|---|---|
| First-line | Diet and exercise changes — reduce refined carbs, regular activity |
| If targets not met (1-2 weeks) | Metformin tablets |
| If still not controlled | Insulin injections — very common and safe in pregnancy |
| Monitoring | Extra growth scans to check baby's size; increased surveillance |
Risks If UntreatedUntreated gestational diabetes increases risk of: a large baby (macrosomia) leading to birth complications, stillbirth, neonatal hypoglycaemia after birth, and future type 2 diabetes for both mother and baby. Good control significantly reduces all these risks.
After the Baby Is BornGestational diabetes usually resolves immediately after delivery. However, having had it means a significantly higher risk (up to 50%) of developing type 2 diabetes later in life. A follow-up glucose test at 6-13 weeks postpartum, then annual HbA1c checks, are recommended.
Will I definitely need insulin?
No — most women with gestational diabetes manage successfully with diet and exercise alone. About 10-20% need metformin or insulin to reach target glucose levels.
Can I have a vaginal birth with gestational diabetes?
Yes, in most cases. Induction of labour around 38-40 weeks is often recommended, especially if blood sugar control is difficult or the baby is measuring large.
Does gestational diabetes affect breastfeeding?
No — breastfeeding is encouraged and may even help reduce the future risk of type 2 diabetes for both mother and baby.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.