Knowledge of Rh (Rhesus) D Blood Group, Risk Factors and Burden of Rh D Alloimmunisation among Female Secondary School Students in Ikorodu, Lagos, Nigeria

Background: Rh (Rhesus) blood group antigen especially D antigen plays a pivotal role in provision of safe blood and safe pregnancy. Antigen mismatch between blood donor and recipient or pregnant woman and the foetus sets the stage for immunohaematological complication such as haemolytic transfusion reaction and haemolytic disease of the foetus and newborn. Individual knowledge of the Rh blood group status among females of reproductive age group is a contributory measure for effective control and prevention of untoward complications of antigen mismatch.

Objective: This study assessed the level of awareness of own Rh D blood group status among female secondary school students, their risk for alloimmunisation, the distribution of Rh D antigen and the burden of alloimmunisation.

Materials and Methods: A cross sectional study of 927 female secondary school students in Ikorodu, Lagos, South-West Nigeria was performed. A multistage sampling technique was used. Ethical approval was granted by Lagos University Teaching Hospital’s (LUTH) Health Research and Ethics Committee and permission granted by Lagos State Ministry of Health. Parental/guardian and student informed assent consent were obtained. Relevant data on socio demographics, knowledge of Rh D blood group, and risk factors for alloimmunisation were collected using a structured interviewer-administered questionnaire. Blood specimen was collected from all participants and tested for Rh D blood group and alloantibody (Anti D) status using standard protocols. Results are presented in frequency tables.

Results: Sixty-eight (7.3%) have heard about Rh blood group system. About 6.7% of the participants described Rh system as an independent system, while 6.5% described the Rh system as a part of ABO antigen system. Of the 122 students who knew their blood group, only 106 (86.9%) were correct about their Rh D status after being tested. Known risk factors for Rh D alloimmunisation such as pregnancy and blood transfusion were observed in 53 (5.7%) of the participants. About 96.7% of the participants were Rh D positive. None of the Rh D negative female students was allo-immunised.

Conclusion: This study observed poor awareness/knowledge regarding the Rh (rhesus) blood group system among secondary school females in Ikorodu Local Government Area of Lagos State, Nigeria. Though, none of the participant was alloimmunised to the Rh D antigen, 5.7% had significant risk factors. Efforts should be directed at improving the awareness/knowledge of the rhesus blood group system and its reproductive implications particularly among female secondary students in Ikorodu, Lagos and other parts of Nigeria.