Korean J Hematol.  2012 Jun;47(2):136-141. 10.5045/kjh.2012.47.2.136.

Changes in hematologic indices in caucasian and non-caucasian pregnant women in the United States

• Harm SK
• Yazer MH
• Waters JH

• KMID: 2083608
• DOI: http://doi.org/10.5045/kjh.2012.47.2.136

Abstract

BACKGROUND
The objective of this study was to determine if there are differences in common red blood cell (RBC) indices and platelet concentrations during pregnancy and to establish if any observed differences in these parameters were based on the patient's ethnicity.
METHODS
From an electronic perinatal database which stores laboratory and clinical information on a large number of births at a regional hospital specializing in obstetrical care, RBC index and platelet concentration data were retrospectively analyzed at various time points throughout pregnancy. RBC index data was collected from 8,277 pregnant women (5,802 Caucasian pregnant women and 2,475 non-Caucasian pregnant women). Platelet concentration data was available from 8252 pregnant women (5,784 Caucasian pregnant women and 2,468 non-Caucasian pregnant women).
RESULTS
Hemoglobin (HGB) levels were significantly higher amongst Caucasian women compared to non-Caucasian women (P at least <0.01) starting at 27 weeks gestation and proceeding until term. There was no significant difference in the mean PLT counts between Caucasian and non-Caucasian pregnant women at any point during gestation.
CONCLUSION
There are ethnic differences in HGB levels, but not the platelet concentrations, during pregnancy. Based on this finding it would be reasonable to conduct formal prospective studies to determine the clinical significance of this difference and to establish the threshold for diagnosing gestational anemia, especially in pregnant non-Caucasian women.

Keyword

Anemia; Complete blood count; Hemoglobin; Pregnancy; Reference Ranges

MeSH Terms

Anemia
Blood Cell Count
Blood Platelets
Electronics
Electrons
Erythrocytes
Female
Hemoglobins
Humans
Parturition
Pregnancy
Pregnant Women
Reference Values
Retrospective Studies
United States
Hemoglobins

Figure

• 

  Fig. 1 Hemoglobin (HGB), hematocrit (HCT), platelet count (PLT), and mean corpuscular volume (MCV) in Caucasian (○) and non-Caucasian (▪) pregnant women throughout the gestational period. Mean±1 SD are shown. See text for statistical analysis. The shaded area on the HGB graph represents the CDC's recommended threshold for anemia during pregnancy.

• 

  Fig. 2 Red blood cell count (RBC), red cell distribution width (RDW), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC), in Caucasian (○) and non-Caucasian (▪) pregnant women throughout the gestational period. Mean±1 SD are shown. See text for statistical analysis.

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