Port Harcourt 

Menstruation interferes with the haematological system. This study assessed some haematological parameters among females at different phases of menstrual cycle namely the premenstrual, menstrual and post menstrual phases.Thirty (30) apparently healthy subjects, ages 15- 45 years were recruited for the study. The parameters analyzed were the Plasma volume, RBC count, Total white blood cell count and differentials. Other parameters were HGB,HCT, MCV, MCHC, Reticulocyte count, RDW and Platelet count. Blood film was also assessed. The microhaematocrit method was used to analyze the PV, Sysmex automated haematology analyzer was used to measure the above-mentioned cell counts and red cell indices. Leishman and New methylene blue staining techniques were used for cell morphology and reticulocyte count respectively. Data generated were statistically analyzed. The mean±standard deviation for the parameters assayed during the PrM, M and PoM phases using ANOVA were as followed, for PV, 60.00±3.00%, 59.00±11.00% and 62.00±9.00% respectively. For RBC Count (HGB, HCT, RBC, MCV, MCH, MCHC, RDW and RC), 12.65±1.14g/d/L, 12.02±2.07g/dL and 12.25±1.83g/dL; 36.00±3.00%, 37.00±8.00% and 35.00±5.00%; 4.42±0.73x1012/L, 4.88±2.90x1012/L and 4.58±0.53 x1012/L; 80.50±6.33fL, 82.05±7.42fL and 78.87±8.14fL; 29.61±3.86pg, 28.31±3.24pg and 27.17±3.48pg; 29.61±3.86g/dL, 28.31±3.24g/dL and 27.17±3.48g/dL; 9.58±6.34%, 13.91±1.60% and 6.93±6.97%; 1.62±1.03%, 2.95±0.97% and 2.51±0.70% respectively. For WBC Count (Total White Blood Cell Count(TWBC) and Differential Count (Neutrophils, Lymphocytes and Mixed)) 5.08±1.34x109/L, 4.08±1.75 x109/L and 5.66±2.06 x109/L; 33.00±15.00 x109/L, 38.00±17.00 x109/L and 46.00±15.00 x109/L; 56.00±17.00 x109/L, 51.00±18.00 x109/L and 47.00±17.00 x109/L; 11.00±5.00 x109/L, 8.00±6.00 x109/L and 10.00±5.00 x109/L respectively. For PC, 268.00±75.00x109/L, 228.00±43.00x109/L and 257.00±69.00x109/L respectively. There was statistically significant difference in RDW, TWBC and PC with p<0.05 and the difference was between the M and PoM phases using Post Hoc Tukey HSD (beta) and no statistically significant difference in the other variables in this study. Also, there was no variation in the cell morphology of WBC and PLT but there was presence of burr cells during the PoM phase. The findings from this study would aid in creating awareness that blood cells could be affected during menstruation, hence there is need for regular medical checkup and supplementation amongst menstruating females.