CGM use in early pregnancy offers ‘window of opportunity’ to improve perinatal outcomes

Key takeaways:

• Women with vs. without large for gestational age neonates or hypertensive disorders of pregnancy had higher mean glucose levels.
• Results were consistent regardless of the presence of gestational diabetes.

Women with fetal overgrowth or hypertensive disorders of pregnancy have notable continuous glucose monitor-derived glycemic patterns detected during early pregnancy, sometimes without a gestational diabetes diagnosis, researchers reported.

“There are limited data on the use of continuous glucose monitoring glycemic profiles in pregnant individuals, both with and without diabetes, and whether continuous glucose monitoring can serve as a valuable tool for identifying glycemic patterns that may signal the potential for adverse perinatal outcomes,” Celeste Durnwald, MD, associate professor of obstetrics and gynecology in the Maternal Fetal Medicine Research Program at the Perelman School of Medicine at the University of Pennsylvania, and colleagues wrote. “The prospect of identifying dysglycemia earlier in pregnancy may provide a window of opportunity for timely intervention to decrease the risk of adverse perinatal outcomes associated with glucose intolerance.”

Durnwald and colleagues conducted a prospective observational study of 760 women with singleton pregnancies and HbA1c levels less than 6.5% from June 2020 to December 2021. All women were enrolled before 17 weeks’ gestation and wore masked continuous glucose monitors consecutively until delivery. Researchers evaluated rates of large and small for gestational age neonates and hypertensive disorders of pregnancy.

Within the cohort, 7.2% had gestational diabetes; mean HbA1c was 5.2%.

Women with vs. without large for gestational age neonates (102 mg/dL vs. 100 mg/dL; P = .01) or hypertensive disorders of pregnancy (103 mg/dL vs. 99 mg/dL; P < .001) had higher mean glucose levels. More time was spent above 120 mg/dL and 140 mg/dL during pregnancy among women with large for gestational age neonates (16% vs. 12%; P = .006 and 3.9% vs. 2.8%; P = .006, respectively) or with a hypertensive disorders of pregnancy (1% vs. 12%; P < .001 and 3.5% vs. 2.8%; P < .001, respectively) compared with women without.

Women with vs. without small for gestational age neonates had lower mean glucose levels (97 mg/dL vs. 101 mg/dL; P = .01) and spent less time above 140 mg/dL (1.6% vs. 2.3%; P = .01) and more time below 63 mg/dL (3% vs. 2.3%; P = .02).

These results remained consistent regardless of presence of gestational diabetes.

“The use of continuous glucose monitoring during early pregnancy may be instrumental in identifying those individuals who are most at risk for perinatal outcomes associated with dysglycemia,” the researchers wrote. “Further investigation is needed to fully understand the role of continuous glucose monitoring in providing an opportunity for early interventions to mitigate these risks.”