Risk of a couple having a child with severe thalassemia syndrome, prevalence in lower northern Thailand.

Thalassemia screening in pregnant women and their spouses was performed at Buddhachinaraj Provincial Hospital and 8 community hospitals in Phitsanulok; lower northern Thailand. The prevalence of thalassemic carrier state was determined of 1,198 couples. Of these, 4.8% had heterozygous alpha thalassemia-1, 1.6% had heterozygous beta thalassemia, 12.4% had heterozygous hemoglobin (Hb) E, 2.7% had homozygous Hb E and 0.25% of others had abnormal Hb. Eighteen at risk couples (1.5%) were identified. Fifteen couples were at risk for compound heterozygous Hb E / beta thalassemia and the remaining 3 were at risk for homozygous alpha thalassemia-1. Prenatal diagnosis (cordocentesis) was performed in 4 couples at risk, but no fetuses with severe thalassemic disease were detected.