Frequent Monitoring of A1C During Pregnancy as a Treatment Tool to Guide Therapy

OBJECTIVE: No guidelines for A1C measurement exist for women with gestational diabetes mellitus (GDM). The aim of this study was to document the rate of A1C decline in women with GDM. RESEARCH DESIGN AND METHODS: Women with GDM in the Santa Barbara County Endocrine Clinic are managed with a carbohydrate-restricted diet and self-monitored blood glucose before and 1-h postprandial. Insulin is started if the preprandial glucose concentration is ≥90 mg/dl and/or a 1-h postprandial glucose concentration is ≥120 mg/dl. Capillary A1C was tested weekly using the DCA2000+ analyzer. RESULTS: Twenty-four women with GDM (aged 29.0 ± 7.3 years) with initial A1C ≥7.0% were recruited. Baseline A1C was 8.8 ± 1.8%. Mean A1C decline was 0.47% per week (range 0.10–1.15%); the maximum was 4.3% in 4 weeks. CONCLUSIONS: This study documents rapid decline in A1C during pregnancy and the utility of weekly A1C to guide therapy.