Central nervous system congenital malformations, especially neural tube defects in 29 provinces, metropolitan cities and autonomous regions of China: Chinese Birth Defects Monitoring Program

Data from the Chinese Birth Defects Monitoring Program (CBDMP) over the period of October 1986 to September 1987 were analysed to study the descriptive epidemiology of congenital malformations of the central nervous system (CNS), especially neural tube defects (NTDs) in China. A total of 4628 CNS congenital malformations were recorded within seven days of delivery among 1,243,284 live and stillbirths of 28 or more weeks gestation in 945 hospitals from all 29 provinces, metropolitan cities and autonomous regions of China. Neural tube defects account for 73.55% of these cases, hydrocephaly for 24.63% and microcephaly for 1.82%. The prevalence rates at birth of NTDs and congenital malformations of the CNS in China were 27.37 and 37.22 per 10,000 respectively. More NTDs were observed in females (35.68 per 10,000 female births) as compared to males (19.23 per 10,000 male births). The prevalence of NTDs in rural areas (51.69 per 10,000 births) was higher than that in urban areas (15.45 per 10,000 births).

[A survey on the constitutional status of perinates in China]

Data of all categories of birth defects among live and still births from 28 weeks of gestation to a period within 7 days after delivery were collected. During a period of 12 months (1986.10-1987.9), there were 1,243,284 perinates monitored in 945 hospitals of 29 provinces, cities and autonomous regions. Among these, 16,172 perinates were with birth defects. Altogether, 101 categories of birth defects were noted. The total incidence of the 101 categories of birth defects in China was 130.1 per 10,000. The 5 leading categories of major birth defects by frequency were: anencephaly, hydrocephaly, spina bifida, cleft lip with cleft palate, and congenital heart diseases. Perinatal deaths totaled 33,137 and the perinatal mortality was 26.7 per 10,000. Among the causes of perinatal death, congenital malformation accounted for 17.8%. There were 44,469 births (35.8%) of full-term low birth weight infants, and 1,748 of them were with birth defects. The incidence of birth defects in full-term low birth weight infants was 393.1 per 10,000.

[Epidemiology of neural tube defects in China]

During a period of 12 months (Oct. 1986 to Sep. 1987), 1,243,284 live and still births from 28 weeks of gestation to a period within 7 days after delivery were monitored in 945 hospitals of 29 provinces, cities and autonomous regions of China. A total of 3,404 cases of neural tube defects were recorded, among which there were 1,891 cases of anencephaly (55.6%), 1,050 cases of spina bifida (30.9%) and 463 cases of encephalocele (13.6%). The incidence of neural tube defects in China varied from 6.6 to 105.5 with a mean of 27.4 per 10,000. A female preponderance (35.7 per 10,000) over the male (19.2 per 10,000) was noted (P less than 0.01). The incidence of neural tube defects in the rural area (51.7 per 10,000) is higher than that in the urban area (15.5 per 10,000), (P less than 0.01).

[Epidemiology of cleft lip and cleft palate in China]

During a period of 12 months (Oct. 1986 to Sep. 1987), 1,243,284 live and still births were monitored in 945 hospitals of 29 provinces cities and autonomous regions of China. A total of 2,265 cases of cleft lip and cleft palate were recorded, of which cleft lip with cleft palate accounted for 61.3%, isolated cleft lip for 30.5% and isolated cleft palate for 8.2%. The incidence of cleft lip and cleft palate in this country varied from 13.4 to 30.7 with a mean of 18.2 per 10,000. The total incidence of cleft lip and cleft palate in the rural area is higher (20.8 per 10,000) than that in the urban area (16.9 per 10,000) (P less than 0.01). A male preponderance (19.8 per 10,000) over the female (16.3 per 10,000) (P less than 0.01) was observed.