Hereditary hematologic disorders (HHDs) originate from genetic factors that cause disruptions of blood homeostasis. The Thalassemia Unit, Najaf province, Iraq, keeps all medical records of all patients with HHD from the Najaf province.

We aimed to conduct an epidemiological study to obtain a comprehensive epidemiological picture concerning sex distribution, and effects of blood groups and consanguinity.

All registered HHD patients (until May 2019) in the Thalassemia Unit (1033 patients, aged 0.5–65 years old) were included in the study.

The prevalence of HHD in Najaf city is 69.60 per 100,000 population. There are significantly more male than female HHD patients (Male=53.437%, Female=46.563%, p=0.019). The top 3 prevalent HHD are transfusion-dependent thalassemia (36.012%), non-transfusion dependent thalassemia (34.656%), and sickle-β thalassemia disorder (13.746%).

The highest percentage of patients were in the centre of Najaf (56.42%), followed by Kufa, Mishkhab, Haidariah, Manathera, and Abbasiya. The distribution of blood groups and Rh factors of HHD patients in the Najaf population was not significantly different from that in the normal population. The consanguinity rate observed in our patients’ parents (78.67%) was significantly higher (p<0.0001) as compared with the consanguinity rate in the population (45.8%).

During the last few years, there was an increase in HHD cases in Najaf city and, therefore, there is an urgent need to increase awareness about the effects of consanguinity marriages on HHD in order to limit the incidence of HHD.