Trimester-specific reference intervals for hemoglobin A1c in non-diabetic pregnancy in a Chinese population

Area of Science:

• Clinical Chemistry
• Reproductive Medicine
• Endocrinology

Background:

• Physiological glycated hemoglobin (HbA1c) reference intervals during pregnancy are not well-defined.
• Accurate HbA1c values are essential for assessing maternal and fetal health outcomes.
• This study addresses the need for trimester-specific HbA1c data in pregnant populations.

Purpose of the Study:

• To determine trimester-specific reference intervals for HbA1c levels.
• To provide essential data for non-diabetic pregnant women in China.
• To support improved clinical management during pregnancy.

Main Methods:

• A cross-sectional study involving 4,134 non-diabetic pregnant women in China.
• HbA1c levels were measured using high-performance liquid chromatography.
• Reference intervals (median and 2.5th-97.5th percentile) were calculated for each trimester (T1, T2, T3).

Main Results:

• Trimester 1 (T1) HbA1c reference interval: 4.0-5.5% (median 4.7%).
• Trimester 2 (T2) HbA1c reference interval: 3.9-5.3% (median 4.5%).
• Trimester 3 (T3) HbA1c reference interval: 4.1-5.7% (median 4.8%).
• Significant differences observed between trimesters (p < 0.0001).

Conclusions:

• Established trimester-specific HbA1c reference intervals for non-diabetic pregnant women in China.
• Upper limits were 5.5% (T1), 5.3% (T2), and 5.7% (T3).
• Highlights the importance of using trimester-specific ranges for optimal maternal and fetal health monitoring.