Frequency of chromosomal trisomies and risk factors

The aim of the study is to evaluate the use of cytogenetic and molecular cytogenetic techniques to prenatal trisomies setting 13 , 18 and 21 of chromosomes for patients during the 2007 to 2011, that had genetic counseling to determine between these trisomies and risk factors.1,156 patients were examined and for 49 (4.2%), abnormal karyotype was identified, of which 30 (61%) are associated with Down syndrome, 14 (29%) to the Edwards syndrome and 5 (10%) are those relating to Patau syndrome. After studying questionnaires and case records data, based on the statistical reliability of the data analysis of fetal abnormality association with the main factors on reproductive (abortions, contraceptives) and other risks or environmental factors (smoking, genetic diseases and drug abuse) was performed.