A base-line survey on birth defects in Gansu province,West China

We report a study to determine the incidence, types and rank order of congenital anomalies and related fetal and infant mortality in Gansu province in China to provide a base-line for an intervention project directed at reducing birth defects in Gansu. Forty-two communities in four counties of Gansu were randomly selected by cluster sampling, based on economic and geographical features of the province. All infants born between 1 January 2001 and 1 January 2002 (live and stillborn) were investigated in departments of gynaecology and obstetrics, in birth control centres and in facilities for women and children in county and community hospitals. The types of birth defect were classified by the diagnostic standardisation ICD-9. The overall incidence of birth defects in Gansu was 15.4/1000 births (102/6621): 6.7/1000 (44) neural tube defects, 4.7/1000 (31) low birthweight infants, 2/1000 (13) limb defects, 0.8/1000 (five) cleft lip and palate and 0.5/1000 (three) Down's syndrome. The infant mortality rate was 14.8/1000 (98), to which birth defects contributed 7.3/1000 (48). We conclude that the incidence of birth defects in Gansu is one of the highest in China, that birth defects are the leading cause of infant mortality and that neural tube defects cause most deaths.