http://www.alliedacademies.org/gynecology-reproductive-endocrinology/ Gynecol Reproduct Endocrinol -UK 2018 Volume 2 Issue 3 2 Research Article Introduction During pregnancy, the total blood volume increases by about 1.5 L. The plasma volume is increase by 25%-80%, reaching its maximum by mid pregnancy. Red cell mass also increases by 10%-20% but the net result is that hemoglobin (Hb) concentration falls. Typically, this is by 1-2 g/dL by the late second trimester. Women who take iron supplements have less pronounced Hb changes, (the increase is approximately 30% over pre-pregnancy values). It is hard to defne a normal reference range for Hb during pregnancy and the limit for diagnosing anemia. The World Health Organization has suggested that anemia is present in pregnancy when Hb concentration is <11 g/dL. However, large studies in healthy Caucasian women taking iron supplements from mid pregnancy found Hb values in the early third trimester to be 10.4-13.5 g/dL (2.5 th -97.5 th centiles). Red cell count and hematocrit (Hct) values are like- wise lower in pregnancy, but the other red cell indices change little. The red cells show more variation in size and shape than in the non-pregnant state. Hemoglobin and hematocrit increase after delivery. Signifcant increases have been documented between measurements taken at 6-8 weeks postpartum and those at 4-6 months postpartum, demonstrating that this length of time is needed to restore them to non-pregnant values [1]. Hemoglobin levels fall in pregnancy as a result of a physiological increase in plasma volume that is greater than the pregnancy-associated increase in red cell mass. Iron stores are exhausted by the end of pregnancy in the majority of women unless iron is given. Iron defciency accounts (IDA) for over 90% of anemia during pregnancy, therefore iron should be the main-stay of therapy. Anemia affects quality of life and virtually all organs. Maternal anemia in infuences mortality, fetal growth, premature death in utero, and fetal programming. Anemia is screened for in pregnancy at booking, 28 weeks and possibly 36 weeks (if the 28-week test result is low). The frequency of testing is dependent on the country of care France, for example, carries out a hemoglobin level at every pregnancy visit. Anemia screening is primarily done by Introduction: During pregnancy women undergo several structural and physiological changes almost in most body systems including the hematological profle. The main reported hematological change is plasma expansion and hemodilution which affect the red blood cells (RBCs) and hemoglobin (Hb) and other indices including packed cell volume (PCV). Objectives: The objectives of this study were to assess the effect of pregnancy on PCV and Hb among Sudanese pregnant women and derive a formula for the normal values in pregnant women in relation to the packed cell volume. Methods: An analytical case control study was conducted in Khartoum state, Sudan 2017. The study included 10 Sudanese pregnant women not taking tonics, 20 Sudanese pregnant women taking tonics attending antenatal care at Omdurman Military hospital and 20 Sudanese non- pregnant women in the same age group as control. A questionnaire was used to collect socio- demographic and clinical data. Blood sample was collected and Complete blood count (CBC) was measured by using automated cell counter Sysmex. Results: The study population comprised 50 women, 10 pregnant women not taking tonics, 20 pregnant women taking tonics and 20 non-pregnant women as control; The results showed a non-signifcant statistically decrease in PCV in women not taking tonic (0.220) when compared to pregnant taking tonics and non-pregnant. There was also non-signifcant statistically decrease in Hb in pregnant women not taking tonic compared to pregnant taking tonics and non-pregnant with P values (0.104). Conclusion: During pregnancy there was statistically decrease in PCV values, and count and by considering the hemodilution factor there was a signifcant increase in values in pregnant ladies not taking tonics. Abstract Effect of pregnancy on packed cell volume and hemoglobin level among sudanese pregnant women attending antenatal care at omdurman military hospital (khartoum state). Mohamed Abdalla Shareef Ahmed 1 , Ibrahim A Ali 2 , Omer A Musa 2* 1 Department of Physiology, Faculty of Medicine, Ibn Sina University, Khartoum, Sudan 2 Department of Physiology, Faculty of Medicine, The National Ribat University, Khartoum, Sudan ISSN: 2591-7994 Keywords: Pregnancy, Hemodilution, PCV, Hemoglobin. Accepted on September 06, 2018