Heterozygous beta-thalassaemia in pregnancy: two rare causes of severe fetal anemia requiring intrauterine blood transfusions

Abstract

Aim

In this article, we present two cases of severe fetal hemolytic anemia based on a beta-thalassaemia trait inherited from a single parent.

Results These cases, presented at 20 and 28 weeks' gestation, necessitated intra-uterine blood transfusions. This occurrence is remarkable because it challenges the common assumption that beta-thalassaemia typically has no prenatal implications regarding fetal anemia. Both fetuses inherited a rare heterozygous mutation from their mother, resulting in gamma-thalassaemia-related anemia. In the first case, the anemia was related to a deletion in the beta locus control region (βLCR) and in the second case, a deletion on chromosome 11p15.4 was the cause. These mutations not only affect the beta chain production, but also the gamma chain production, leading to a reduction in the synthesis of HbF, ineffective erythropoiesis and consequently, perinatal hemolytic anemia. Conclusion Clinicians should be vigilant regarding these rare mutations in families with a history of beta-thalassaemia as the fetal clinical consequences can be severe and intra-uterine blood transfusions may prove life-saving for these fetuses.