Chromosomal factors of infertility in candidate couples for ICSI: an equalrisk of constitutional aberrations in women and men

To assess the frequency of chromosomal aberrations in French candidates for intracytoplasmic sperm injection (ICSI), and to explore the existence of a female chromosomal factor in some cases of couple infertility, a collabora tive retrospective clinical and cytogenetic study was performed, launched b y the Association des Cytogeneticiens de Langue Francaise (ACLF), The karyo types of 3208 patients [2196 men (68.4%), 1012 (31.6%) women] included in I CSI programmes over a 3-year period in France were collected. A total of 18 3 aberrant karyotypes was diagnosed, corresponding to an abnormality freque ncy of 6.1% (134/2196) for men and 4.84 % (49/1012) for women. The followin g frequencies of abnormalities were observed respectively for men and women : 1.23 % (n = 27) and 0.69% (n = 7) for reciprocal translocations, 0.82% (n = 18) and 0.69% (n = 7) for Robertsonian translocations, 0.13% (n = 3) and 0.69% (n = 7) for inversions, 3.32% (n = 73) and 2.77% (n = 18) for numeri cal sex chromosome aberrations, and 0.59% (n = 13) and 0 % for other struct ural aberrations. Among the male patients of this latter group, 0.40 % (n = 9) had a Y chromosome abnormality, Among the male patients with numerical sex chromosome abnormalities, 2.23 % (n = 49) were 47,XXY, 0.32% (n 7) were 47,XYY, and 0.77% (n = 17) had a mosaicism for numerical sex chromosome an omalies. All the female patients with sex chromosome abnormalities (2.77 %, n = 28) had mosaicism for numerical sex chromosome anomalies. Even if thes e cases-the significance of which was sometimes questioned-were disregarded in the analysis, 2.08% (21/1012) of abnormal karyotypes remained in women. An overall increased frequency of chromosomal aberrations was found, and t his confirmed that in some cases of poor reproductive outcome there may be a contribution of maternal chromosome aberrations. Indeed, the existence of a chromosome abnormality in the female partner was associated with the gro up of infertile men in which there was no apparent cause of infertility.