Introduction: Although it has been generally admitted that we know the cause of congenital malformations in about 40% of the cases, these data are based on very few studies.
Patients and methods: Here we present the distribution of 22,784 malformed infants in our country by type of cause of their defects.
Results: Our results show a great impact of chromosomal alterations in causing congenital anomalies. On the other hand, performing the chromosomal study will enable the diagnosis of genetic entities, as well as environmental ones that are clinically similar to the clinical patterns produced by chromosomal abnormalities.
Conclusions: We can recognize the cause of congenital defects in a proportion higher than the 40% which is generally accepted. Nowadays, there is no reason that justifies not performing a chromosomal study with high resolution band techniques in infants with congenital defects.