Association of blood parameters in early pregnancy with anemia during late pregnancy: a multicenter cohort study in China

Abstract

Background

Low-hemoglobin concentration and anemia are important risk factors for the health and development of women and children. The aim of this study was to investigate the correlation between blood indicators in early pregnancy among non-anemia women and anemia in the third trimester among pregnant women in China with uncomplicated pregnancies >36 weeks.

Methods

This was a multicenter, prospective cohort study. Pregnant women registered at the survey hospitals from May 2019 to December 2020 were included and followed up until delivery and discharge. The predictive value of serum ferritin (SF) and routine blood indexes (platelet count, red blood cell count, hemoglobin level, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration) were analyzed using a receiver operating characteristic (ROC) curve for the occurrence of anemia in the third trimester.

Results

The area under the ROC curve of the first trimester hemoglobin for predicting anemia during late pregnancy (cutoff value 128 g/L, sensitivity 82.3%, specificity 49.6%) and iron deficiency anemia (cutoff value 124 g/L, sensitivity 66.3%, specificity 66.4%) in the third trimester was larger than those of other blood variables.

Conclusions

Hemoglobin levels in the first trimester were significantly better predictors of anemia during the third trimester than the other indices. Our study contributes to the clinical practice of early intervention for anemia, thus taking effective measures to improve maternal and infant outcomes.

Keywords:

• Anemia
• pregnancy
• hemoglobin
• ferritin
• China
• predictors

Funding

This study was supported by National Key Research and Development Program of China (2021YFC2701501). This work was not associated with any commercial entity.

Author contributions

Yue Zeng participated in the study design, data collection, statistical analyses and was a major contributor in writing the manuscript. Guolin He conceived of the whole study, supervised the work overall, and carried out the study design and corrections of the manuscript. Both authors approved the final manuscript for submission.

Ethical statement

This study was approved by the Medical Ethics Committee of the West China Second Hospital of Sichuan University (project approval number: 2016-009). All participants provided written informed consent at enrollment.

Transparency declaration

The contributing authors affirm that this manuscript is an honest, accurate, and transparent account of the study being reported and no important aspects of the study have been omitted.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data presented in this study are available upon request from the corresponding author. The data are not publicly available to protect patients’ privacy.