Continuous Interstitial Glucose Monitoring through a Long-Term Subcutaneous Implantable Sensor during Pregnancy in Type 1 Diabetes: A Two- Patient Case Report

Introduction: Optimal glycaemic control is crucial during pregnancy in women with type 1 diabetes mellitus (T1D). Current guidelines, based on positive data from the CONCEPTT (Continuous Glucose Monitoring in Pregnant Women With Type 1 Diabetes Trial), on maternal glycaemic control and fetal outcomes, recommend offering real-time Continuous Glucose Monitoring (rt-CGM) as a standard method in all pregnancies of women with type 1 diabetes (T1D). Case presentation: In these two clinical cases, we describe for the first time the gestational outcomes in two patients with T1D who chose to maintain a long-term implantable subcutaneous sensor (Eversense XL®) as a CGM method during their pregnancies. The first case concerns a 33- year-old young woman with a 25-year history of T1D on Continuous Subcutaneous Insulin Infusion (CSII), who faced her first pregnancy with a suboptimal preconception glycaemic control; the second case describes the second pregnancy of a 37-year-old patient with a more recently diagnosed T1D, on multiple daily injection (MDI) therapy who achieved adequate glycaemic compensation before planned conception. Conclusion: The subcutaneous sensor replacement was carried out at the beginning and end of the 2nd trimester, respectively, without any complications, allowing optimal monitoring and adjustment of insulin dose and achieving optimal glucose targets throughout the pregnancy until delivery.