ARE CONGENITAL-MALFORMATIONS INCREASING - A COMPARATIVE-STUDY OF 2 PERIODS - (1971-1977 AND 1982-1991, AT THE MATERNITY OF UNIVERSITY-OF-CHILE CLINICAL HOSPITAL)

The aim of this work was to analyze the global incidence of congenital malformations at the Maternity of University of Chile Clinical Hospit al in the periods between 1971 and 1977 and between 1982 and 1992. A s ignificant and sustained increase in incidence was observed in the fir st period from 10. 64 per 1000 born alive in 1971 to 33.79 in 1977. In the second period, the rates were stabilized at 60 to 70 per 1000 bor n alive. When comparing the incidence of 20 major or easily diagnosed malformations in the two periods, there was a significant increase in all during the second period. The possible causes of the increase in i ncidence are discussed, such as better diagnosis and registry, the use of ultrasound diagnosis and the incorporation of stillbirths to the r egistry during the second period.