Table 1: Demographic and hematologic parameters among first and second groups of donors.
| 
 
 Parameters  | 
 
 First group (donation < 6) (n = 50)  | 
 
 Second group (donation ≥ 6) (n = 44)  | 
 
 p-value 
  | 
| 
 Age (Years)  | 
 31.7 ± 7.8  | 
 33.9 ± 7.4  | 
 0.17  | 
| 
 BMI (Kg/m2)  | 
 24 ± 3.9  | 
 25 ± 2.5  | 
 0.07  | 
| 
 SBP (mmHg)  | 
 119 ± 9  | 
 117 ± 19  | 
 0.41  | 
| 
 DBP (mmHg)  | 
 77.7 ± 5.5  | 
 76 ± 6.5  | 
 0.18  | 
| 
 Hb (g/dL)  | 
 15.1 ± 1.3  | 
 15.2 ± 1.3  | 
 0.72  | 
| 
 RBCs (× 1012/L)  | 
 5.6 ± 0.55  | 
 5.7 ± 0.62  | 
 0.32  | 
| 
 HCT (%)  | 
 47.3 ± 2.8  | 
 47.8 ± 4.2  | 
 0.53  | 
| 
 MCV (fL)  | 
 85.3 ± 5.3  | 
 82 ± 14  | 
 0.15  | 
| 
 MCH (pg)  | 
 29.4 ± 2.8  | 
 28.7 ± 3.5  | 
 0.31  | 
| 
 MCHC (g/dL)  | 
 34.3 ± 1.6  | 
 34.4 ± 2.6  | 
 0.92  | 
| 
 RDW-CV (%)  | 
 14.7 ± 1.3  | 
 15.3 ± 2.1  | 
 0.07  | 
| 
 WBCs (× 109/L)  | 
 6.8 ± 2.4  | 
 6.3 ± 2.3  | 
 0.27  | 
| 
 PLTs (× 109/L)*  | 
 275 (257-295)  | 
 263 (245-288)  | 
 0.44  | 
| 
 Ferritin (ng/mL)*  | 
 81 (65-100)  | 
 76 (62-95)  | 
 0.70  | 
Data are presented as mean ± SD, *Data are presented as geometric mean (95% confidence interval) evaluated by Independent-Samples T test.