CD28 and hydrops fetalis: Eight immunophenotypes demonstrated an increased risk of HF, including immunoglobin D+ (IgD+) CD38br absolute cell (AC); double positive (CD4+CD8+) %leukocyte; CD28− CD127− CD25++ CD8br %T cell; CD28− CD127− CD25++ CD8br %CD8br; CD28+ CD45RA+ CD8br %T cell; CD19 on IgD+ CD38br; CD27 on IgD− CD38dim; CD45 on lymphocyte.