The effect of maternal factors on blood sugar control in patients with diabetes in pregnancy
Poster #: 101
Session/Time: B
Author:
Katherine Hayley Pepper, BS
Mentor:
Marwan Ma'ayeh, MD
Research Type: Clinical Research
Abstract
Objective To identify clinical and demographic factors associated with suboptimal glycemic control, as defined by Time in Range (TIR) from continuous glucose monitoring (CGM), in pregnant individuals with Type 2 or Gestational Diabetes (GDM).
METHODS:
The records of all type 2 diabetic and GDM patients who had CGM between 2016 and 2025 were reviewed and data abstracted. Glycemic control was categorized based on third-trimester TIR into three groups: optimal (TIR ≥75%), suboptimal (TIR >50-75%), and poor (TIR ≤50%). We used multivariable multinomial logistic regression to identify factors associated with suboptimal and poor control. A sensitivity analysis was then performed exclusively on the Type 2 diabetes cohort to assess the impact of first-trimester HbA1c on third-trimester glycemic control.
RESULTS:
The analysis included 130 individuals with Type 2 diabetes and 27 with GDM. In the overall cohort, having Type 2 diabetes was the only significant independent predictor of not achieving optimal glycemic control and maternal baseline characteristics did not have a significant impact (Table 1). Compared to individuals with GDM, those with Type 2 diabetes had significantly higher odds of having suboptimal control (aOR 4.62, 95% CI 1.56-13.67; p=0.006) and poor control (OR 3.34, 95% CI 1.04-10.73; p=0.042). In the sensitivity analysis of individuals with Type 2 diabetes, a higher first-trimester HbA1c was the only factor significantly associated with poor glycemic control in the third trimester, after adjusting for maternal age, ethnicity, BMI, and chronic hypertension (aOR 1.46, 95%CI 1.10-1.93; p=0.009 for TIR ≤50% vs ≥75%).
CONCLUSION:
Pregnant individuals with Type 2 diabetes are at a significantly higher risk for suboptimal glycemic control compared with those with GDM. Within this high-risk group, an elevated first-trimester HbA1c associated with worse blood sugar control later in pregnancy, highlighting a critical opportunity for early and intensified management. Variable TIR >50-75% vs >75% TIR 0-50% vs >75% Odds Ratio 95% CI p-value Odds Ratio 95% CI p-value Intercept 0.39 0.04 - 3.58 0.398 0.32 0.09 - 1.19 0.088 BMI 1.00 1.00 - 1.00 0.894 0.97 0.93 - 1.02 0.279 Non-Hispanic/ Latino ethnicity 2.68 0.76 - 9.47 0.126 0.86 0.25 - 2.91 0.801 Maternal age 0.98 0.92 - 1.04 0.448 0.98 0.92 - 1.04 0.518 Chronic hypertension 1.03 0.46 - 2.31 0.951 0.52 0.18 - 1.47 0.214 First trimester HbA1c 1.15 0.90 - 1.47 0.258 1.46 1.10 - 1.93 0.009 R2 / R2 adjusted 0.057 / 0.050 Table 1: Multinomial multivariable regression evaluating the effects of patient variables on TIR BMI: body mass index; CI: Confidence Interval; HbA1c: hemoglobin A1c; TIR: time in range
METHODS:
The records of all type 2 diabetic and GDM patients who had CGM between 2016 and 2025 were reviewed and data abstracted. Glycemic control was categorized based on third-trimester TIR into three groups: optimal (TIR ≥75%), suboptimal (TIR >50-75%), and poor (TIR ≤50%). We used multivariable multinomial logistic regression to identify factors associated with suboptimal and poor control. A sensitivity analysis was then performed exclusively on the Type 2 diabetes cohort to assess the impact of first-trimester HbA1c on third-trimester glycemic control.
RESULTS:
The analysis included 130 individuals with Type 2 diabetes and 27 with GDM. In the overall cohort, having Type 2 diabetes was the only significant independent predictor of not achieving optimal glycemic control and maternal baseline characteristics did not have a significant impact (Table 1). Compared to individuals with GDM, those with Type 2 diabetes had significantly higher odds of having suboptimal control (aOR 4.62, 95% CI 1.56-13.67; p=0.006) and poor control (OR 3.34, 95% CI 1.04-10.73; p=0.042). In the sensitivity analysis of individuals with Type 2 diabetes, a higher first-trimester HbA1c was the only factor significantly associated with poor glycemic control in the third trimester, after adjusting for maternal age, ethnicity, BMI, and chronic hypertension (aOR 1.46, 95%CI 1.10-1.93; p=0.009 for TIR ≤50% vs ≥75%).
CONCLUSION:
Pregnant individuals with Type 2 diabetes are at a significantly higher risk for suboptimal glycemic control compared with those with GDM. Within this high-risk group, an elevated first-trimester HbA1c associated with worse blood sugar control later in pregnancy, highlighting a critical opportunity for early and intensified management. Variable TIR >50-75% vs >75% TIR 0-50% vs >75% Odds Ratio 95% CI p-value Odds Ratio 95% CI p-value Intercept 0.39 0.04 - 3.58 0.398 0.32 0.09 - 1.19 0.088 BMI 1.00 1.00 - 1.00 0.894 0.97 0.93 - 1.02 0.279 Non-Hispanic/ Latino ethnicity 2.68 0.76 - 9.47 0.126 0.86 0.25 - 2.91 0.801 Maternal age 0.98 0.92 - 1.04 0.448 0.98 0.92 - 1.04 0.518 Chronic hypertension 1.03 0.46 - 2.31 0.951 0.52 0.18 - 1.47 0.214 First trimester HbA1c 1.15 0.90 - 1.47 0.258 1.46 1.10 - 1.93 0.009 R2 / R2 adjusted 0.057 / 0.050 Table 1: Multinomial multivariable regression evaluating the effects of patient variables on TIR BMI: body mass index; CI: Confidence Interval; HbA1c: hemoglobin A1c; TIR: time in range