| Abstrakt: |
A detailed analysis is presented of both the individual and collective laboratory findings in 179 pregnant Rh-negative women. The study was under-taken in order to determine the relationships which might exist between the serologic data observed in the mothers and the clinical conditions found in the infants born to them, with the ultimate purpose of presenting the obstetrician with an antepartum interpretation of the significance of the laboratory findings in Rh-negative patients. 1.1. In order to facilitate the expression of the end results and significance of iso-immunization in pregnancy, the collective data were classified and studied according to the Rh characteristic and clinical outcome of the infant: Group I—normal Rh-negative infants; Group II—normal Rh-positive infants; Group III—Rh-positive infants with subclinical hemolytic disease of the newborn; and Group IV—Rh-positive infants with frank hemolytic disease of the newborn.2.2. Of 61 Rh-negative women delivered of normal Rh-negative children, 9 showed isolated low titers of Rh agglutinins ante partum.3.3. The isolated occurrence of Rh antibodies of low titer in Rh-negative women having Rh-positive husbands may be significant under circumstances where evidence of immunization occurs early in pregnancy or where blocking antibodies mask the Rh agglutinins. Apparently spurious positive tests for Rh antibodies may be due to the “carry-over” phenomenon or to pregnancy itself.4.4. Antibody formation occurred more often among multiparous than among primiparous women. Nevertheless, it is important to test Rh-negative women repeatedly for Rh antibodies, regardless of parity. The ease with which some individuals may become immunized and the fact that an opportunity for previous immunization may have been forgotten influences the results of the tests in primiparous women.5.5. Rh-antibody trends were determined for all women showing development of sensitization and their possible significance is shown in relation to the outcome of the child. In general, no patient demonstrating a high antepartum titer of either antibody, especially if their presence were detected early in pregnancy, was delivered of a clinically normal Rh-positive infant.6.6. A comparison of the occurrence of Rh agglutinin and blocking antibodies indicates that no definite cause and effect relationship between them can be inferred from our data. There appears to be an apparent reciprocity between the titer trends of these two antibodies, the significance of which is not entirely clear. The Rh agglutinin appears to be demonstrable in the maternal serum by the twentieth week ante partum. The blocking antibody follows the appearance of the Rh agglutinin and may not be present in demonstrable amounts earlier than about the tenth week ante partum.7.7. The hypothesis is suggested that blocking antibody may be produced, not as a defense for the mother as is Rh agglutinin, but as a protection for the erythrocytes of the fetus. |
