Chromosomal abnormalities are more common in the first trimester abortions. We aimed to investigate the types and prevalence of chromosomal abnormalities in couples with recurrent first trimester miscarriages in Sivas, Turkey.

Three hundred couples (600 individuals) who had a story of recurrent abortion were included in the study. Chromosome analysis was performed after the preparation of lymphocyte culture with the standard method. Karyotype analyses were supported by FISH and aCGH studies.

Total 26 chromosome abnormalities (8.7%) were found in the couples (19 females and 7 males). Fifteen cases (57.7%) were structural anomalies and eleven cases (42.3%) were numerical chromosomal aberrations. We detected 5 balanced translocations (33.3%), 4 Robertsonian translocations (26.7%), 3 inversions (20%), 2 duplications (13.3%) and one deletion (6.7%) among the structural anomalies. Mosaic monosomy X in five cases (45.4%), the combination of mosaic monosomy-trisomy X in three cases (27.3%), the combination of mosaic monosomy-trisomy and tetrasomy X in two cases (18.2%) and mosaic pentasomy X in only one individual (9.1%) were encountered as numerical chromosome aberrations. 19 cases had heterochromatic changes or other chromosomal variations (satellite increments and inv9).

Chromosome analysis in couples with recurrent miscarriage is necessary for possible preimplantation genetic diagnosis. As well as numerical and structural chromosome abnormalities, some chromosomal variations (heterochromatin and satellite increments etc.) may also contribute to recurrent miscarriages. Numerical chromosomal abnormalities are often associated with sex chromosomes and usually seen in females.