Applications To Maternalfetal Medicine

Alloimmunization against the RhD antigen during pregnancy is the most frequent cause of hemolytic disease of the newborn (HDN). Immunization occurs when fetal cells, carrying antigens inherited from the father, enter the mother's circulation following fetal-maternal bleeding. The mother, when not expressing the same antigen(s), may produce IgG antibodies toward the fetal antigen, and these antibodies can pass through the placenta causing a diversity of symptoms, ranging from mild anemia to death of the fetus. Apart from antibodies in the RhD blood group antigen, other specificities within the Rh system and several other blood group antigens can give rise to HDN, but RhD is by far the most immunogenic.1-25-1

Prenatal determination of fetal RhD status is desirable in pregnancies to prevent sensitization and possible hydrops fetalis in fetuses of RhD-negative mothers with RhD-positive fathers. Fetal DNA has been detected in amniotic cells, chorionic villus samples, and, as recently reported, in maternal plasma.[26-32] Polymerase chain reaction amplification of RHD in maternal plasma may be useful for the management of RhD-negative mothers of RhD-positive fetuses and for the study of fetal-maternal cell trafficking.

Before interpreting the results of DNA analysis, it is important to obtain an accurate medical history and to establish whether the study subject is a surrogate mother and whether she has been impregnated with nonspousal sperm.

The discovery of fetal DNA in maternal plasma has opened up new and exciting possibilities for the nonin-vasive prenatal determination of fetal blood group status. However, a number of technical issues still need to be addressed and large-scale multicenter clinical trials need to be carried out. When these issues are resolved, it is likely that the prenatal testing of fetal blood group type will be carried out routinely and safely.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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