Automated Insulin Delivery in Pregnancies Complicated by Type 1 Diabetes: A Real World Observational Study of Available Systems

BACKGROUND: Only one automated insulin delivery (AID) system is licensed in Australia for use in pregnancies complicated by Type 1 diabetes (T1D); however, some women using other AID systems have continued to use these 'off-label' in pregnancy. Usage patterns from a single centre in Australia will be of interest to clinicians supporting women with T1D in pregnancy. AIMS: This is an observational study evaluating outcomes in women treated with different AID systems through a pregnancy cared for at a tertiary maternity centre. MATERIALS AND METHODS: All women using AID in one or more trimesters of pregnancy through a 3-year study period are included in the reporting of glycaemic and insulin delivery measures in each trimester of pregnancy. All women using AID throughout the duration of a pregnancy within the study period are included in the reporting of birth outcomes. RESULTS: Four AID systems had been used during the study period, MiniMed with Smartguard, T:slim with Control IQ, YpsoMed with CamAPS and Omnipod with SmartAdjust. Small numbers of YpsoMed and Omnipod users precluded these from statistical analysis. Women using MiniMed and T:slim AID systems differed in terms of early HbA1c and smoking history with MiniMed users representing suboptimal pre-pregnancy diabetes control. Use of continuous glucose monitoring (CGM) was additionally significantly lower for users of the MiniMed system. Median pregnancy-specific time in range (pTIR) was above 62% for all systems by trimester 2 and above 64% for all systems by trimester 3 with no significant difference between MiniMed and T:slim systems. There was less pregnancy-specific time below range (pTBR) and/or time well below range (pTWBR) for the MiniMed system in all trimesters compared with the T:slim system. CONCLUSIONS: AID systems without the tight target considered necessary for pregnancy were still able to achieve good glycaemic outcomes.