Glucose Treatment Targets in Pregnancy - A Review of Evidence and Guidelines

Background: Maternal diabetes mellitus during pregnancy is associated with an increased risk of pregnancy complications for both the mother and the fetus. One of the most prevalent complications is pathological fetal growth, and particularly infants are born large for gestational age (LGA), which leads to problematic deliveries, including the need for caesarean section, instrumental delivery, and further perinatal complications. Glucose monitoring during pregnancy is essential for ensuring appropriate glycaemic control and to reduce these associated risks. The current methods of glucose monitoring include measuring glycosylated haemoglobin (HbA1c), selfmonitoring of capillary blood glucose (SMBG), and more recently, continuous glucose monitoring (CGM). Observational studies and randomised controlled trials (RCTs) have assessed the appropriate glycaemic targets for HbA1c, SMBG, and CGM in relation to pregnancy outcomes.

Objective: In this review, we have identified current international guidelines on glycaemic targets and reviewed the supporting evidence.

Methods: We performed an extensive literature search on glycaemic targets in pregnancies affected by diabetes, and we researched international guidelines from recognised societies.

Results and Conclusion: The majority of studies used to define the glucose targets associated with the best pregnancy outcomes, across all modalities, were in women with type 1 diabetes. There were limited studies on women with type 2 diabetes and gestational diabetes. We, therefore, suggest that further research needs be conducted on glucose targets and clinical outcomes, specifically in these populations where CGM technology offers the greatest potential for monitoring glucose and improving pregnancy outcomes.