Gestational diabetes (GDM) – the essentials
- Who to test: risk-factor screening (prior GDM, BMI >30, previous macrosomic baby, first-degree relative with diabetes, higher-risk ethnic family origin).
- Diagnosis (75 g OGTT): fasting ≥5.6 mmol/L OR 2-hour ≥7.8 mmol/L.
- Common targets (capillary): fasting ≤5.3, 1-hour ≤7.8, 2-hour ≤6.4 mmol/L (confirm local maternity pathway).
Management + escalation (time-critical)
- First: dietitian input + lifestyle plan + home glucose monitoring.
- If targets not met promptly: add metformin (if appropriate) and escalate to insulin if still above target or metformin not tolerated—coordinate with the maternity diabetes team.
- Escalate urgently if: vomiting, ketones, severe hyperglycaemia, intercurrent illness, or reduced fetal movements.
Postnatal follow-up (the bit that leaks)
- Test: HbA1c (or fasting glucose per local pathway) at ~6–13 weeks postpartum, then annual diabetes surveillance.
- Counsel: recurrence risk in future pregnancies + long-term type 2 diabetes risk; offer weight/activity support.
Frequently asked questions
How quickly should I escalate if lifestyle doesn’t work?
Pregnancy is time-sensitive. If readings remain above target after a short trial (often 1–2 weeks, or sooner if markedly elevated), escalate via the maternity diabetes team.
Transparency
This page is an educational, clinician-written summary of publicly available NICE guidance intended for trained healthcare professionals. It uses original wording (not copied text) and should be used alongside the full NICE source, local pathways, and clinical judgement. Doses provided are for general reference; always check the BNF/SPC.