A pregnant woman at 28 weeks with pre-gestational Type 1 diabetes has HbA1c 9.2% in the first trimester. Based on the HAPO study, her offspring's risk profile is BEST characterised by which finding?
- A U-shaped relationship between maternal glycaemia and macrosomia
- B Linear increase in cord C-peptide, birth weight, and neonatal hypoglycaemia with rising maternal glucose ✓
- C Maternal HbA1c has no correlation with neonatal adiposity
- D Fetal hyperinsulinism occurs only when maternal glucose exceeds 200 mg/dL
Correct answer: B. Linear increase in cord C-peptide, birth weight, and neonatal hypoglycaemia with rising maternal glucose
Explanation
The HAPO (Hyperglycemia and Adverse Pregnancy Outcome) study (NEJM 2008) demonstrated a continuous, linear, dose-response relationship between maternal glucose levels (fasting, 1-hour, and 2-hour OGTT values) and adverse outcomes including large-for-gestational-age birth weight, primary caesarean delivery, cord C-peptide >90th percentile (fetal hyperinsulinism), and neonatal hypoglycaemia — with no clearly safe threshold. This was the evidence base for the IADPSG 2010 criteria for GDM diagnosis (single-test OGTT using lower cut-offs than the older Carpenter-Coustan criteria).
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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