This prospective observational study examined the performance of the Dexcom G6 CGM (G6) System in pregnant women with type 1 diabetes (T1D), type 2 diabetes (T2D), or gestational diabetes (GDM).
Participants wore up to two G6 Systems on either the abdomen, upper buttock, and/or back of the upper arm for 10 days. Participants completed one six-hour clinic session between days 3 -7 of the sensor wear period, with venous blood sampling every 30 minutes for comparison of G6 values to paired YSI comparator glucose values. Meals and snacks were consumed as desired. Performance was evaluated using the %20/20 accuracy (proportion of CGM values that were within ±20% of paired YSI values >100mg/dL or within ±20 mg/dL of YSI values ≤100 mg/dL), the mean absolute relative difference (MARD), and the proportion of matched pairs within Zone A of the Clarke Error Grid (clinical accuracy).
Of the 32 participants enrolled, twenty-one (65.6%) and eleven (34.4%) subjects were in the 2nd and 3rd trimesters, respectively. Twenty subjects (62.5%) had T1D, 9 (28.1%) had GDM, and 3 (9.4%) had T2D; 26 (81.3%) were using insulin, and 17 (53.1%) were active CGM users. The overall %20/20 accuracy, overall MARD, and clinical accuracy were 92.5%, 10.3%, and 90.2%, respectively. Accuracy was acceptable across glycemic ranges and was best on the upper arm. There were no device-related adverse events.
This study demonstrated that G6 is accurate and safe across various wear sites in pregnant women with diabetes during their 2nd or 3rd trimesters.