Prenatal control of nondeletional α-thalassemia: first experience in mainland China.

Objective: To demonstrate the performance of nondeletional α-thalassemia prevention at a mainland Chinese hospital.

Methods: A prenatal control program for nondeletional hemoglobin H (Hb H) disease was conducted from January 2010 to June 2012. All couples were screened for α-thalassemia trait, and for couples in whom one partner was tested positive for α(0) -thalassemia, the other was subjected to screening for Hb Constant Spring and Hb Quong Sze mutations. Prenatal diagnoses were offered in pregnancies of couples at-risk for nondeletional Hb H disease.

Results: Of the 30,152 couples screened, 18 (0.06%) were diagnosed as at risk for nondeletional Hb H disease. There were other 13 at-risk couples who were referred to prenatal diagnosis because they had previously an affected child. Of the 31 cases with prenatal invasive tests, 11 (35.5%) had diagnosis by chorionic villous sampling, and 20 (64.5%) had amniocentesis. Totally, 12 fetuses were diagnosed with nondeletional Hb H disease, and all of the affected pregnancies were terminated.

Conclusion: Implementation of a prevention and control program accompanying with a referral system for prenatal diagnosis is technically feasible in southern China, and a number of nondeletional Hb H disease have been prevented during the past 3 years of operation.