Malformations congénitales et catégories socio-professionnelles.

: A case-control study was conducted in a maternity hospital, in order to look for the relationships between the occurrence of birthdefects and the socio-occupational status of the parents. Cases were 189 new-born children with one or several congenital malformations diagnosed at birth or within the first 8 days of the life. Birthdefects were listed according to the British Paediatric Association classification of diseases. Controls were 5,896 new-born children without any congenital malformation detected within the first 8 days of life. Cases and controls were all children born in the same maternity hospital, between 1980 and 1983. The socio-occupational status (INSEE classification) of the parents of cases and controls was ascertained within the first trimester of the pregnancy, before a possible congenital malformation was known. In order to look for the relationships between the socio-occupational status of the parents and the occurrence of birthdefects, we compared the proportions, in each of the socio-occupational classes, of the fathers and of the mothers of cases and controls. These comparisons (for all birthdefects together and for the most frequent ones) were tested using the chi-square test, when the expected number was greater than 5, and the Fischer's test, when it was equal to, or lower than 5. The incidence rate of birthdefects in this sample was 3,1%. Their distribution according to the types of malformations did not differ from that observed in 1982 among the new-borns in Paris. There was no significant difference between the parents of cases and controls, for: age, degree of instruction, ethnic origin, marital status.(ABSTRACT TRUNCATED AT 250 WORDS)