Masked hypoglycemia in pregnancy

Area of Science:

• Endocrinology
• Obstetrics
• Perinatology

Background:

• Hypoglycemia hinders glycemic control in gestational diabetes mellitus (GDM) managed with insulin.
• Continuous glucose monitoring (CGM) can estimate masked hypoglycemia in pregnancy.

Purpose of the Study:

• To estimate masked hypoglycemia in pregnant women with GDM on insulin using CGM.
• To compare masked hypoglycemia between GDM and euglycemic pregnant women.

Main Methods:

• Recruited 20 GDM and 10 euglycemic pregnant women (24-36 weeks gestation).
• Assessed masked hypoglycemia using 72-hour CGM and self-monitoring of blood glucose (SMBG).
• Stratified hypoglycemic episodes based on interstitial glucose levels (2.28-2.77 mmol/L and ≤2.22 mmol/L).

Main Results:

• Masked hypoglycemia detected in 35% of GDM cases and 40% of controls via CGM.
• GDM cases spent more time with glucose levels ≤2.2 mmol/L compared to controls.
• Babies born to GDM mothers were significantly lighter than controls (2860 vs 3290 g).

Conclusions:

• Masked hypoglycemia is present in both euglycemic pregnant women and those with GDM on insulin.
• Masked hypoglycemia did not correlate with adverse maternal or fetal outcomes.
• Low glucose levels may be a physiological adaptation in pregnancy, exaggerated in GDM on insulin.