Continuous Glucose Monitoring in Pregnant Women With Type 1 Diabetes (CONCEPTT): A Multicentre International Randomized Controlled Trial

Abstract

(Lancet 2017;390:2347–2359) Pregnant women with type 1 diabetes are at increased risk of preeclampsia, cesarean delivery, congenital anomalies, and other adverse pregnancy outcomes. While optimal glycemic control during pregnancy can improve outcomes, it is difficult to accomplish due to the complexity of insulin dose adjustments, changes in insulin sensitivity, and variability of insulin absorption that all occur during pregnancy. Continuous glucose monitoring (CGM) has been successful at improving glycemic control in nonpregnant women but studies in pregnant women have had conflicting results. This study aimed to evaluate the effects of CGM in women with type 1 diabetes who were pregnant or planning to become pregnant.

Day-and-Night Closed-Loop Insulin Delivery in a Broad Population of Pregnant Women With Type 1 Diabetes: A Randomized Controlled Crossover Trial

“…Second, the small sample size of this phase 2a study meant that we lacked statistical power for anything other than the power calculation assumption of a 30% between-group difference. Recent results from a CGM trial in 215 T1D pregnancies suggested that even small differences (a 7% increase in time in target and 5% reduction in hyperglycemia in the Continuous Glucose Monitoring in Pregnant Women With Type 1 Diabetes Trial [CONCEPTT]) are associated with substantial (;50%) reductions in neonatal complications (5). The current study was underpowered to detect small differences.…”

“…Thus, the primary focus of treatment in a T1D pregnancy is to reduce fetal exposure to hyperglycemia without increasing maternal hypoglycemia. Recent evidence has suggested that although continuous glucose monitoring (CGM) improves day-to-day glucose control, with ;1 h/day less hyperglycemia in women who use multiple daily injections (MDIs) and continuous subcutaneous insulin infusion (CSII), optimal maternal glycemia is not achieved (5).…”

“…Even with increasing use of new CGM and CSII technologies, pregnant women with T1D continue to spend, on average, 8h/day hyperglycemic (5,6).Furthermore, two-thirds of T1D offspring have complications related to maternal hyperglycemia, including large for gestational age and preterm delivery, which contribute to high rates of neonatal intensive care unit admissions (4,5).…”

Continuous Glucose Monitoring: A Review of Recent Studies Demonstrating Improved Glycemic Outcomes

“…There have been numerous studies of CGM in pregnancy. [43][44][45][46][47][48] Use of CGM during pregnancy has been reported to improve quality of glycemic control, but does not reduce the risk of macrosomia. 46,47 Additional randomized trials have been initiated.…”

“…46,47 Additional randomized trials have been initiated. 48 Hospitalized patients. Usage of CGM in the hospitalized patient and in the ICU remains a work in progress.…”