Distribution of Abnormal Haemoglobin Variants and ABO/Rhesus Blood Groups Among Pregnant Women Attending Antenatal Care at Imo State University Medical Center, Owerri, Nigeria

Background: Hemoglobinopathies and blood group incompatibilities are significant genetic and immunopharmacological concerns in prenatal care, particularly in sub-Saharan Africa. The presence of abnormal hemoglobin variants such as sickle cell trait (AS) and their potential implications for maternal and fetal health underscore the need for early screening and targeted interventions during pregnancy. Similarly, ABO and Rhesus (Rh) blood group incompatibilities can result in adverse outcomes, including hemolytic disease of the newborn, if not promptly identified and managed. Objective: This study was conducted to assess the prevalence and distribution of hemoglobin variants and ABO/Rh blood groups among pregnant women attending antenatal care at the Imo State University Medical Center, Nigeria. Methods: A cross-sectional study involving 100 pregnant women was carried out at the Imo State University Medical Center. Blood samples were collected and analyzed to determine hemoglobin variants and Rh D status using standard electrophoresis and serological methods. The frequency distribution of ABO blood groups, Rh D antigen, and hemoglobin genotypes was documented and analyzed. Results: The results revealed that 92% of the participants had the normal hemoglobin genotype AA, while 8% had the AS genotype, indicating carriers of the sickle cell trait. No cases of AC, CC, SS, or SC hemoglobin variants were identified. ABO blood group distribution showed that Blood Group O was most prevalent (58%), followed by Blood Group A (20%), Blood Group B (17%), and Blood Group AB (5%). In terms of Rhesus status, 96% of the women were Rh D positive, while 4% were Rh D negative. A breakdown of Rh D status across blood groups indicated that Blood Group O had the highest Rh D positive prevalence (56%) and Rh D negative (2%), followed by Group A (19% Rh D positive, 1% Rh D negative), Group B (16% Rh D positive, 1% Rh D negative), and Group AB (5% Rh D positive only). Conclusion: The study highlights a predominance of the AA hemoglobin variant and Rh D positive blood type among pregnant women in this population, with Blood Group O being the most common. These findings underscore the importance of routine hemoglobinopathy screening and Rh factor determination during antenatal care. Incorporating genetic counseling and targeted health strategies tailored to local genetic profiles can significantly enhance maternal and neonatal outcomes in this region.