Gestational Diabetes Mellitus Flashcards
Why is GDM clinically important?
- It’s common and becoming more common
- Adverse pregnancy outcomes
- It’s easy and cheap to Dx and Tx
- Long-term health implications are costly
What’s Diabetes?
Series of conditions associated w hyperglycemia and caused by defects in insulin secretion and/or action
What are the 4 major types of DM?
- Type 1 DM
- Type 2 DM
- GDM
- Specific types of DM (Cystic fibrosis, Steroid use, Pancreatitis)
What’s GDM?
Diabetes occurring in pregnancy that is not clearly overt diabetes
What’s the Pederson Hypothesis?
- Maternal Hyperglycemia
- Fetal Hyperglycemia
- Fetal Hyperinsulinism
- Fetal Macrosomia
What’s the prevalence of GDM?
- 16.6% Pregnancies affected by diabetes
- 84% of that 16.6% is GDM
- The rest is DM T1 or T2
What are the 3 Modifiable risk factors of GDM?
- BMI >30 kg/m2 or significant WG in early adulthood and between pregnancies
- Excessive gestational weight gain during first 18-24 weeks
- HDL <0.9 mmol/L, triglycerides >2.82 mmol/L
What are the 3 Red Flags for risk factors in GDM?
- Previous unexplained perinatal loss or birth of a malformed infant
- Glycosuria at the first prenatal visit
- Multiple gestation
What are the 6 Non-Modifiable risk factors in GDM?
- History of glucose intolerance or GDM in previous pregnancy
- Hispanic/African/ Native American, South/East Asian, Pacific islander
- Family history of diabetes, especially in first-degree relatives
- Older maternal age (>30 y/o)
- Previous birth of an infant >4000g (~9 pounds)
- Medical condition/setting associated w development of diabetes, such as metabolic syndrome, PCOS, current use of glucocorticoids, HTN/CVD, acanthosis nigricans
What patients are at lower risk of GDM?
- Young (<25 y/o)
- Non-Hispanic White
- Normal BMI (<25 kg/m2)
- No history of gluc intolerance or adverse pregnancy outcomes
- No 1st degree relative w diabetes
10-30% meet all of these criteria
What are the risks and benefits of GDM screening?
-MisDx of GDM can lead to increased anxiety, pregnancy interventions, and implementation of treatment w/o clear benefit to the mother and her offspring
-Cost-effective in populations w high prevalence of GDM and T2DM, provided that lifestyle interventions are applied
Save $1945 per patient
What’s the screening method for GDM in Ireland?
-1-Step Fasting OGTT between 24-28 weeks
-One abnormal value needed for Dx
* 0h ≥ 5.1 mmol/L
* 1h ≥ 10 mmol/L
* 2h 8.5 mmol/L
What’s the screening method for GDM in the US?
-2-Step
1) 50g 1h Glucose Challenge (random)
* < 7.1 mmol/L = No GDM
* 7.2-11 mmol/L = Further Testing Needed
* ≥ 11.1 mmol/L = GDM
2) 100g 3h Glucose Challenge (fasting)
-2 Abnormal values to Dx GDM
* 0h ≥ 5.3 mmol/L
* 1h ≥ 10 mmol/L
* 2h ≥ 8.6 mmol/L
* 3h ≥ 7.8 mmol/L
What is HbA1c?
-Glycated haemoglobin. Glucose is attached to the N-terminal valine residue of each b-chain of haemoglobin A (HbA)
-Glucose can also attach nonenzymatically to the lysine residue within haemoglobin
What are the established HbA1c ranges per trimester?
- T1: 29-37 mmol/mol
- T2: 25-35 mmol/mol
- T3: 28-39 mmol/mol
