Prevalence of Rhesus Negative Status Amongst Antenatal Atendees in the University of Uyo Teaching Hospital, Uyo, Nigeria: A 5-Year Review

Abstract

Introduction: The Rhesus (Rh) antigen is the most polymorphic of human blood group systems second only to the ABO in transfusion and transplantation medicine with significance in iso-immunization which can cause haemolytic disease of the foetus and newborn. This study was carried out to determine the prevalence of Rhesus negativity amongst antenatal clinic attendees in the University of Uyo Teaching Hospital. Methodology: This was a 5-year retrospective study carried out between March 1st, 2012 and February 28th, 2017. Data containing the ABO and Rhesus blood group of all antenatal clinic attendees was collected from the Laboratory registers and analysed using Microsoft excel. Results: The prevalence rate of Rhesus D negative women was 4.40%. The average yearly attendance was 2861 women. The commonest blood group was O with 8232 (57.54%), followed by blood group A, 3416 (23.88%) and blood group B, 2388 (16.69%) while the least common blood group was AB, 271 (1.89%). Most Rhesus D-negative women were of blood group O; 382 (60.78%), followed by group A; 142 (22.58%), and blood group B was 94 (14.49%). AB blood group was the least; 11 (1.70%). Sensitization rate among the 629 Rhesus D-negative women was 1.11%. Conclusion: The prevalence of rhesus negativity is low in the population studied with an ABO distribution that mirrored the antenatal population, hence the overall need for immunoprophylaxis. It is however very necessary to educate and counsel all non-sensitized Rhesus negative women on the need for antenatal and post-partum immuno-prophylaxis as well as public enlightenment on the rationale for Rhesus typing, especially among women.