Ba&;s hydrops fetalis is lethal because
Ba hydrops fetalis is a lethal complication of alpha thalassemia trait where oxygen can&;t release from hemoglobin. Hb Bas is formed of 4 gamma chains. The oxygen affinity is so high that it releases very little oxygen into the fetal tissues. Reference: Ghai essential of pediatrics, eighth edition, p.no:342
Hb Ba's cannot bind oxygen
The excess a - globin form insoluble precipitates
Hb Ba's cannot release oxygen to fetal tissues
Microcytic red cells become trapped in the placental
Hematology