Gestational and family risk factors for carriers of congenital heart defects in southern Brazil.

Background: Congenital heart disease (CHD) is a serious threat to public health. Despite this, its etiology is poorly understood and few cardiac teratogens have been defined. The aim of the present study was to identify gestational and family risk factors for CHD in a sample of patients from a pediatric hospital in southern Brazil.

Methods: A prospective and consecutive sample from subjects with or without CHD, hospitalized at a pediatric intensive care unit, was enrolled. All patients with CHD underwent a GTG-banding karyotype. Chromosomal abnormalities were observed in 47 subjects (15.8%), and these were excluded from the study. The final sample consisted of 250 CHD subjects and 303 controls.

Results: After statistical analysis, using logistic regression, the variables age, rural location, gestational loss, use of anti-hypertensive medication, antibiotics and alcohol in the first trimester of pregnancy were all independently associated with CHD. These results were similar to those of some studies and different from others. It should be noted, however, that, for several variables, the data in the literature as well as the present study were insufficient to determine risk.

Conclusions: Some differences found may be explained by genetic factors and sociocultural diversity. In contrast, because CHD consists of a heterogeneous group of lesions, the etiology may vary. The standardization of research data and classification of methods for future studies are essential.