[Central nervous system malformations in a Clinical Hospital of Universidad de Chile and in Chilean maternity hospitals that participated in the Latin American Collaborative Study of Congenital Malformations (ECLAMC)].

BACKGROUND: In Chile, the rates of central nervous system congenital malformations at birth remain high, when compared with the rest of the world.

AIM: To report the rates of central nervous system congenital malformations in Chilean hospitals.

MATERIAL AND METHODS: Using the ECLAMC protocol, every malformed newborn or stillbirth, weighing more than 500 g at birth is registered using a standard protocol, and the next non malformed child of the same sex born in the same hospital is assigned as control.

RESULTS: The rates of central nervous system congenital malformations are higher at the University of Chile Clinical Hospital than in the rest of Chilean hospitals or Latin American Hospitals. There are significantly higher rates of anencephalia in Concepcion and spina bifida in Valdivia, Rancagua and Concepcion. In the University of Chile Clinical Hospital, global annual rates have a negative slope of -0.0259 per 1000 born alive, with a correlation coefficient of -0.125 (p < 0.05). The slope is positive among children born alive, with an annual rate increase of 0.071. Among stillbirths, the slope is -0.47 per 1000 born alive. Sixty two percent of malformed children were female. Among children with neural tube defects, 30% had a malformed relative and, of these, 66% had the same malformation.

CONCLUSIONS: Family clustering of neural tube defects, supports the influence of a genetic factor influencing their appearance.