Type and frequency of chromosome aberrations in 781 couples undergoing intracytoplasmic sperm injection

Cytogenetic investigations were performed ire 781 couples prior to intracyt oplasmic sperm injection (ICSI) because of severe male infertility or ferti lization failures in previous in-vitro fertilization attempts. Out of these 1562 patients, 1012 had a normal karyotype without any aberrations (64.8%) , 204 patients had an abnormal karyotypes (13.1%), These chromosome aberrat ions included constitutional aberrations (4.4%), fragile sites of autosomes (3.0%), low level mosaicism of sex chromosomes (4.0%) and secondary struct ural chromosome aberrations (4.2%), Combinations of different types of abno rmalities were stated, Another 346 patients (22.1%) showed single cell aber rations; the significance of these is unclear at the moment. Constitutional chromosome aberrations were detected in 69 patients. The following chromos ome aberrations were observed: 35 sex chromosomal aberrations (comprising h yperploidies of X or Y chromosomes, mosaicisms and derivative X and Y chrom osomes), 34 autosomal aberrations including 14 reciprocal translocations, f ive Robertsonian translocations, six inversions, one marker chromosome, one trisomy 18 mosaicism and seven other structural aberrations. Three autosom al regions showed fragile sites: 6q13 in 2.9% of the patients, 17p12 and 10 q24 in 0.05 % each. In conclusion, our data show that a high number of infe rtile couples in an ICSI programme are affected by chromosome aberrations w hich occur in both sexes. It is suggested that a chromosomal. analysis shou ld be performed on both partners before ICSI treatment is initiated.