To Show the Effectiveness of Anti-D Gammaglobulin in Preventing Rhesus Isoimmunization in Rhesus

Abstract

During the two year period of the study period, a total of 6885 antenatal mothers were booked to the antenatal clinic. Out of these, 280 (4.1%) were found to be Rhesus negative with 193 (69~) being no immunized and 87 (31%) immunized. The study group for the objective set out therefore consisted of 193 subjects. 117 mothers out of these 193 delivered at Kenyatta National Hospital. Two of the mothers had miscarriages in early 2nd trimester,74 of the mothers delivered in other institutions, 40 had no babies' blood group and Rhesus typed; 16 (13.7%) had Rhesus negative babies and 61 (52%) had Rhesus positive babies , This last group was the most important as far as the objective of the study was concerned. Within 48 hours after delivery Kleihauer' Test was done on 37 of these 61.Rhesus positive babies’, mothers, and on 27 of the 40 unknown cases. Six Kleihauer Tests were also performed on mothers who later turned out to be Rhesus negative; since the babies' blood group results would he delayed at times beyond 48 to 72 hours. The final results obtained at the completion of investigation on each subject, i.e. 6 months, are shown in a flow diagram in the results. The conclusion from the study is that 250mg of anti-D immunoglobulin protects our African mothers against isoimmunization. However, due to ethical reason, a control group for the study was used. The outcome of pregnancy in both immunized and unimmunized groups was also considered although this was not included in the protocol. It is found that babies and placenta of affected mothers were of smaller weights and big weights respectively than those of unaffected Rhesus negative mothers or normal Rhesus positive mothers. Affected Mothers were 21so found to be older (mean age 29 years) and of a higher parity (mean 3.7) than the unaffected Rhesus-negative, and the normal Rhesus positive ones. This was expected since risk of Immunization increases with succeeding parity and higher parity is associated with old age.