Abstract
Trimester specific reference ranges of hematological indices were described in several populations; however, comparable reports among Sudanese women with normal pregnancy are lacking. To evaluate trimester pattern of change and reference ranges of hematological profile among Sudanese women with normal pregnancy, we followed 143 women with singleton gestation since early pregnancy until the third trimester in Saad Abu-Alela Hospital, Khartoum, Sudan, during the period of January-December 2015. Obstetrics and medical history was gathered using questionnaire and hematological profile was investigated using hemo-analyser. The first, second and third trimester mean (SD) [5
th
-95
th
centile] of hematological profile were as follow: RBC counts 4.30 (0.36) [3.69-4.93], 4.35 (0.36) [3.69-4.93], 4.08 (0.44) [3.44-4.78] ×10
6
/mm
3
; hemoglobin concentration 10.81 (1.22) [8.92-12.74], 10.62 (0.93) [9.00-12.10], 10.83 (1.13) [8.82-12.60] g/dL; hematocrit 35.38 (3.52) [30.12-40.30], 34.43 (2.51) [30.58-38.23], 35.17 (3.18) 29.66-40.04] %; WBC counts 7.69 (1.96) [4.36-11.20], 8.45 (1.97) [5.48-12.13], 8.36 (2.11) [5.00-11.96] ×10
3
/mm
3
; platelet counts 278.02 (66.93) [182.6-418.0], 251.96 (64.17) [163.8-381.8], 238.36 (57.10) [150.4-346.2] ×10
3
/mm
3
. The present study is the first to establish trimester specific, reference range for hematological profile among Sudanese women with normal pregnancy. The trimester reference range of RBC, WBC and platelets and other hematological indices are mostly parallel to international records.