The ABO and Rh factor blood systems are important in humans because they are involved in blood transfusion and immunogenetics. Human beings are characterized by the A, B, AB and O blood groups that are determined by the type of antigen on erythrocytes. These blood antigens are part of the ABO blood system. The Rh factor blood system has been shown to have about 50 types of blood antigens that are found on RBCs. The most important among the antigens are the D, E, e, C and c proteins. The D antigen is used to define individuals who are Rh positive or negative (Rath et al., 2012). If a person has D proteins on his or her erythrocytes, then he or she is said to be Rh positive. However, if a person does not have the D antigen on his or her RBCs, then he or she is said to be Rh factor negative. Rh factor incompatibility has been a major issue that has been causing problems in newborns (Smits-Wintjens et al., 2012).
If a woman who lacks Rh factor conceives with a man who has Rh factor, then her immune system would form Rh factor antibodies in response to the D antigens that are introduced into the mother’s bloodstream. This only happens if the blood of the fetus and mother mixes. Thereafter, antigen-antibody reaction occurs. This reaction culminates in the destruction of the fetus’s erythrocytes, a process that leads to hemolytic anemia (Rath et al., 2012). However, sensitization of a mother’s immune system cannot happen during the first pregnancy because the amount of antibodies produced is too small to initiate a harmful antibody-antigen reaction. However, antibody-antigen reaction is common during subsequent pregnancies. The following conditions could also lead to sensitization of the mother’s immune system to form Rh factor antibodies: miscarriage, blood transfusion, pregnancy outside the womb (ectopic pregnancy), induced abortion, and villus sampling of the chorion (Rath et al., 2012; Smits-Wintjens et al., 2012).
Sensitization of a mother’s immune system could be known by conducting a test to establish the blood type and Rh factor. Also, a test can be done to show whether a woman has formed antibodies against the Rh factor positive blood. If tests prove that a woman could develop Rh factor antibodies, then she would be injected with Rh factor immunoglobulin to prevent sensitization. The injection is given during pregnancy and after child delivery. When appropriate tests are done early during pregnancy, it is recommended that Rh factor immunoglobulin injection be given at the 28th week of pregnancy. When a Rh factor negative woman delivers a Rh factor positive baby, the mother should be given a dose of Rh immunoglobulin to prevent sensitization of her immune system (Smits-Wintjens et al., 2012). The immunoglobulin should be given for each pregnancy, regardless of whether it was offered during previous pregnancies. Also, the treatment should be provided to women who have abortion, ectopic pregnancies, and miscarriages. Blood transfusion should be given to a fetus while in the womb or immediately after birth if it is established that a Rh factor negative woman has developed Rh antibodies (Smits-Wintjens et al., 2012).
In conclusion, hemolytic disease is a serious condition that is caused by destruction of baby’s RBCs by mother’s Rh antibodies. Blood type and Rh factor antibody tests would help a pregnant woman take appropriate actions regarding her Rh factor status. Rh factor immunoglobulin is the preferred medication for preventing sensitization of a woman’s immune system. Blood transfusion would be required if a woman is found to have formed antibodies that destroy a fetus’s RBCs.
References
Rath, M. E. A., Smits‐Wintjens, V. E. H. J., Oepkes, D., van Zwet, E. W., Van Kamp, I. L., Brand, A.,… & Lopriore, E. (2012). Thrombocytopenia at birth in neonates with red cell alloimmune haemolytic disease. Vox sanguinis, 102(3), 228-233.
Smits-Wintjens, V. E., Rath, M. E., Lindenburg, I. T., Oepkes, D., van Zwet, E. W., Walther, F. J., & Lopriore, E. (2012). Cholestasis in neonates with red cell alloimmune hemolytic disease: incidence, risk factors and outcome. Neonatology, 101(4), 306-310.