Hydrops fetalis is a serious, life-threatening condition in which the fetus has an abnormal accumulation of fluid in the tissues around the heart, lungs, abdomen, or under the skin.

Thalassemia is an autosomal recessive genetic disease. Thalassemia is divided into two main types: alpha and beta thalassemia, depending on which gene mutation causes deficiency in the synthesis of alpha or beta hemoglobin chains.

Fetal blood transfusion is a dangerous complication of pregnancy. If not treated early, this condition can cause fetal mortality of 90% - 100% or leave severe sequelae for the child.