Anormalidades cromossômicas em casais com história de aborto recorrente

Abstract

To asses the prevalence and clinical characteristics of couples with history of recurrent spontaneous abortion and chromosome abnormality, attended at the present service. All the couples referred to our service due to history of recurrent spontaneous abortion, from January 1975 to June 2008, were evaluated. Only the ones whose chromosome karyotype analysis by GTG bands has been successfully made were included in the study. Clinical data on their age, as well as on the number of abortions, stillbirth, multiple malformations, livebirth per couple, and the result of the karyotype exam were collected. Fisher's exact test (p<0.05) has been used to compare the incidence of chromosome alterations found in our study, with data in the literature. There were 108 couples in the sample. Their ages varied from 21 to 58 years old among the men (average of 31.4 years old), and from 19 to 43 among the women (average of 29.9 years old). In ten couples, one of the mates (9.3%) presented chromosome alterations, which corresponded respectively to three cases (30%) of reciprocal translocation [two of t(5;6) and one of t(2;13)], two (20%) of Robertsonian translocation [two of der(13;14) and one of der(13;15)], five(50%) of mosaicism (mos) [two cases of mos 45,X/46,XX, one of mos 46,XX/47,XXX, one of mos 46,XY/47,XXY and one of mos 46,XY/47,XYY] and one (10%) of chromosome inversion [inv(10)]. In one of the couples, the female presented two concomitant alterations: t(2;13) and der(13;14). Chromosome abnormalities were found in 5% of the couples with a history of two abortions, in 10.3% with three abortions, and in 14.3% with four or more abortions. The incidence of chromosome abnormalities seen in our study (9.3%) was similar to most of the studies carried out in the last 20 years, varying from 4.8 to 10.8%. Nevertheless the high percentage of patients with mosaicism in our sample, has called our attention. It is believed that this fact may be associated to the high number of metaphases ordinarily analyzed in the present service.