Gestational diabetes
Diabetes diagnosed for the first time during pregnancy. Usually resolves after delivery but raises lifetime risk of type 2 diabetes by ~50%. Tight control during pregnancy protects mother and baby.
What it is
Gestational diabetes mellitus (GDM) is glucose intolerance with onset or first recognition during pregnancy. Placental hormones (especially human placental lactogen) drive maternal insulin resistance, and in susceptible women the pancreas can't keep up. About 7–10% of pregnancies are affected globally, more in some populations. Untreated GDM raises risks of macrosomia (large baby with shoulder-dystocia risk), neonatal hypoglycaemia and respiratory distress, pre-eclampsia, caesarean delivery, and stillbirth. After delivery glucose usually normalises, but the mother carries a ~50% lifetime risk of developing type 2 diabetes — making postpartum screening essential.
Key lab markers
- 75-g oral glucose tolerance test (OGTT) at 24–28 weeks — the diagnostic standard in most countries. Diagnosis if any value crosses: fasting ≥92, 1-h ≥180, 2-h ≥153 mg/dL.
- Fasting glucose — early-pregnancy screen for pre-existing diabetes (≥126 mg/dL).
- HbA1c — useful pre-pregnancy or first-trimester (a value ≥6.5% reflects pre-existing diabetes rather than GDM).
- Postpartum 75-g OGTT at 6–12 weeks after delivery and then every 1–3 years lifelong.
Symptoms
Usually silent — that's why universal screening is recommended. When symptomatic:
- Excessive thirst, frequent urination
- Fatigue
- Recurrent vaginal or urinary infections
- Large fundal height for gestational age (detected by obstetrician)
When to discuss with a doctor
Universal screening with the 75-g OGTT at 24–28 weeks of pregnancy is the standard of care in most countries. Diagnosed GDM warrants obstetric and diabetes-team co-management — usually starting with dietary advice and self-monitored blood glucose; insulin or metformin if targets are not met. Postpartum 75-g OGTT at 6-12 weeks is essential — it catches the 5–10% who remain diabetic after delivery and resets the baseline for lifelong surveillance. Mediora.AI flags the diabetes-pattern labs; pregnancy management belongs with obstetrics.