Chromosomal abnormalities in recurrent miscarriages by conventional karyotyping analysis

Abstract Objectives: to describe the prevalence and types of chromosomal abnormalities in couples with recurrent miscarriage and products of conception. Methods: electronic searches were performed in the PubMed/Medline database and in the Portal Regional da Biblioteca Virtual em Saúde/BVS (Regional Website of the Virtual Library in Health/BVS) using the descriptors “chromosomal abnormalities and abortions and prevalence”. After applying the inclusion and exclusion criterias, 17 studies were selected. Results: 11 studies were conducted in couples with recurrent miscarriage and six in products of conception. The main results of the couples with recurrent miscarriage were: the frequency of chromosomal abnormalities which varied from 1.23% to 12% and there was a predominance alteration of the chromosomal structures (reciprocal translocations, followed by Robertsonian). In products of conception, the results observed were: the frequency of chromosomal abnormality was above 50% in approximately 70% of the studies; there was a predominance alteration of the numerical chromosomal (trisomy - chromosomes 16, 18, 21 and 22, followed by polyploidy and monosomy X). Conclusions: in summary, cytogenetic alterations represent an importante cause of pregnancy loss and its detection can help couples with genetic counseling. Therefore, the value of knowledge on the prevalence of cytogenetic abnormalities in miscarriage samples is unquestionable, once it is permitted a proper genetic counseling for the couple. Resumo Objetivos: descrever a prevalência e os tipos de anormalidades cromossômicas em casais com aborto recorrente e em produtos de concepção. Métodos: foram realizadas buscas eletrônicas nas bases de dados PubMed/Medline e no Portal Regional da Biblioteca Virtual em Saúde/BVS usando os descritores "chromosomal abnormalities and abortions and prevalence". Após a aplicação de critérios de inclusão e exclusão, 17 estudos foram selecionados. Resultados: 11 estudos foram realizados em casais com aborto recorrente e seis em produtos de concepção. Os principais resultados em casais com aborto recorrente foram: a frequência de anormalidades cromossômicas variou de 1,23% a 12% e houve predomínio de alterações cromossômicas estruturais (translocações recíprocas, seguidas por Robertsonianas). Nos produtos de concepção, os resultados observados foram: a frequência de anormalidade cromossômica foi acima de 50% em aproximadamente 70% dos estudos; houve predomínio de alterações crom