Background: Patients with diabetes and impaired awareness of hypoglycemia (IAH) are at increased risk of severe hypoglycemia (SH). IAH is increased during pregnancy. To date, maternal and neonatal outcomes of pregnant women with hypoglycemia unawareness or SH has not been well described.

Aim: To examine maternal and neonatal outcomes in women with IAH compared to women with normal awareness of hypoglycemia (NAH).

Methods: We included 214 pregnant women with type 1 diabetes who participated in the CONCEPTT trial. Participants completed Hypoglycemia Fear Surveys (HFS-II) at baseline and study completion. Post-hoc analysis of data was conducted using logical regression analysis to estimate the odds of occurrence of events by IAH versus NAH. The role of continuous glucose monitoring (CGM) use on outcomes was also examined.

Results: Overall, 30% of participants reported IAH (n=64). Women with IAH had more episodes of SH during pregnancy (mean 0.44 vs. 0.08, p<0.001). Women with IAH scored significantly higher on the HFS-II worry scale (25.9 vs. 20.1, p 0.0036), indicating more fear of hypoglycemia at baseline. They also spent more time below range (<63 mg/dl) at 12 weeks gestation. Higher overall HFS-II scores were associated with a higher risk of maternal SH episodes (RR 1.78, 95% CI 1.39-2.27) and a lower incidence of neonatal hypoglycemia (OR 0.597, 95% CI 0.385-0.893). There were no other differences in obstetric/neonatal outcomes between women with IAH and NAH. Higher HFS-II scores were associated with more diabetes-related complications, such as nephropathy (OR 1.907, 95% CI 1.06-3.4), independent of duration of diabetes. Finally, CGM did not affect incidence of SH (RR 0.54, 95% CI 0.12 - 2.16).

Conclusion: In pregnant women with type 1 diabetes, IAH is associated with more maternal SH episodes and more fear of hypoglycemia. Fear of hypoglycemia was associated with reduced neonatal hypoglycemia as well as more maternal diabetes-related complications.


J. Bahrami: None. G. Tomlinson: None. H.R. Murphy: Advisory Panel; Self; Medtronic. D. Feig: Advisory Panel; Self; Novo Nordisk A/S. Speaker’s Bureau; Self; Medtronic.


JDRF; Canadian Clinical Trial Network

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