Patient‐led rapid titration of basal insulin in gestational diabetes is associated with improved glycaemic control and lower birthweight

AIMS: Elevated fasting blood glucose in gestational diabetes (GDM) is a key predictor of high birthweight babies and adverse pregnancy outcomes but is hard to treat. We implemented a simple, patient‐led, insulin dose titration algorithm aiming to improve fasting glycaemic control in GDM. METHODS: In women with GDM, initiating basal insulin, we recommended a daily four‐unit dose increase after every fasting glucose value ≥5.0 mmol/mol (90 mg/dl). This approach augmented our pre‐existing intensive (weekly) specialist nursing input. Using a before‐and‐after retrospective observational study design, we examined insulin doses and glucose values at 36 weeks gestation and maternal and neonatal outcomes in 105 women completing pregnancy before and 93 women after the intervention. RESULTS: The baseline characteristics of women in the before and after groups were the same. Women initiated on insulin after implementation (n = 30 before, n = 43 after) achieved substantially higher doses at 36 weeks (53 vs. 36 units/day; 0.56 vs. 0.37 units/kg/day; p = 0.027). 36‐week mean fasting glucose was lower in those on insulin after implementation (4.6 vs. 5.1 mmol/L [83 vs. 92 mg/dl]; p = 0.031). Birthweight was significantly reduced (birthweight Z‐scores 0.34 vs. 0.92; p = 0.005). There was no significant difference in macrosomia (after; 2% vs. before; 17% p = 0.078) or caesarean sections (after; 33% vs. before; 47%; p = 0.116). No women experienced severe hypoglycaemia. There were no outcome differences before versus after intervention in women not treated with insulin. CONCLUSIONS: Patient‐led daily insulin titration in gestational diabetes leads to higher insulin dose use lower fasting glucose and is associated with lower birthweight without causing significant hypoglycaemia.