Congenital malformations are a known cause of intrauterine death; of them, congenital heart diseases (CHDs) are accountable for the highest fetal and neonatal mortality rates. They are strongly associated with other extracardiac malformations and an early fetal mortality. Two hundred and twenty fives cases of CHDs are presented. Of them, 155 were isolated CHDs (group A) and 70 were associated with extracardiac malformations, chromosomal disorders, or genetic syndromes (group B). The overall mortality in group B was higher than that observed in group A (p <0.01). Prenatal mortality was similar in both groups: A: 8.4% (13 out of 155); B: 15.7% (11 out of 70). Postnatal mortality was A: 16.8% (26 out of 155) (p <0.01), OR: 0.52 (95% CI: 0.16-1.7); B: 32.9% (23 out of 70) (p <0.01), OR: 0.41 (95% CI: 0.20-0.83). Heart diseases associated with extracardiac abnormalities had a higher mortality rate than isolated congenital heart diseases in the period up to 60 weeks of postmenstrual age (140 days post-term). No differences were observed between both groups of patients in terms of prenatal mortality.