Drug-Induced Hydrops in the Fetal Lamb

In an effort to produce an experimental biologic model simulating human erythroblastosis and hydrops fetalis, fetal lambs were exsanguinated slowly or were treated with a hemolytic agent. Although fetal anemia did result, no hydrops was observed. When a protein inhibitor was added to the treatment, hydropic changes were produced more consistently even though there was no measurable decrease in the fetal plasma protein concentration.