The objectives of this proposed research are as follows: 1. to salvage the life of the otherwise doomed Rh affected infants by developing the technique of plasmapheresis to remove maternal antibody and thus lower maternal antibody titer. 2. Rh disease is generally one of progressive severity with each subsequent pregnancy. We will attempt to stop this progression by administering currently licensed Rho Immune Globulin following the delivery of the first affected infant. This is in addition to our ongoing clinical trial of Rho Immune Globulin for prevention of Rh disease with clinical follow-up through repeated subsequent pregnancies. 3. New experiments will be set up to test suppression of endogenous antibody production by passively injected antibody. The aim is to develop another method of management of the Rh sensitized mother, which would also have direct clinical implication in other medical endeavors, such as organ transplants, etc. 4. To improve and expand on our present knowledge and experience of fetal transfusions, spectrophotometric analysis of amniotic fluid and to search for additional clues in liquor specimens that will help us diagnose with greater accuracy the current and future condition of the unborn child. To this end we already have the world's largest collection of frozen human amniotic fluid specimens, each fully labeled and with corresponding complete clinical history and outcome.