Neonatal screening of phenylketonuria and congenital hypothyroidism in China.

Mass screening of newborns for some congenital metabolic diseases is a tremendous achievement in the field of preventive medicine. The pilot study of neonatal screening in China was started in 1981. According to the results of 1.1 million newborn screenings from 8 big cities in the past 6 years, the incidence of phenylketonuria was 1/14,767 and congenital hypothyroidism was 1/5,469. China is a vast country with great economic differences among the different regions, making neonatal screening difficult in some areas. The national neonatal screening coverage rate is only about 2 % at the moment, but in metropolitan centers like Shanghai, the coverage rate reached 95 % in 1997.