Rhesus Negative Pregnancy: Prevalence and Foetomaternal Outcomes in a Tertiary Hospital, South-South Nigeria

Abstract

Rhesus incompatibility can pose a problem in pregnancy and cause obstetric failure in a handful of women. The Rhesus factor is a red blood cell surface antigen; and there are many antigen subtypes that make up the Rhesus blood group systems, of which the most commonly involved and most immunogenically associated with Rhesus isoimmunisation is the D antigen. The objective of this study is to determine the prevalence of Rhesus negativity and the foetomaternal outcomes at the Federal Medical Centre, Yenagoa, Bayelsa State, Nigeria. This was a 5-year retrospective study conducted between 1st January, 2016 and 31st December, 2020 at our Obstetric Unit. Data were retrieved, entered into a pre-designed preformed and analyzed using SPSS version 25.0. Results were presented as mean and standard deviation for continuous variables and frequencies or percentages for categorical variables. Of the 4,571 pregnant women, 104 were Rhesus negative, giving a rate of 2.27%. The most common blood group among the women (53.8%) and their partners (84.6%) was the O blood group. Only 2 (1.9%) women were sensitised. Out of the 104 Rhesus negative women, 81 were unsensitised (77.9%) and received anti-D immunoglobulin. Majority of the babies had a good outcome, though 19 (18.2%) of them were admitted into the special care baby unit for various conditions. The incidence of Rhesus negative pregnancy in our study was 2.27%, and 1.9% of the women were sensitised. Prompt administration of anti-D immunoglobulin after sensitising events and post-delivery is key in the prevention of Rhesus isoimmunisation.