ABSTRACT
PURPOSE: This study was conducted to determine the frequency and contribution of chromosomal abnormalities in miscarriages and in couples with recurrent in vitro fertilization/intra cytoplasmic sperm injection (IVF/ICSI) failure. MATERIALS and METHODS: A total of 221 individuals; 79 with three or more recurrent spontaneous abortions and 142 with at least three IVF/ICSI failures. Chromosomal analysis from peripheral blood lymphocytes was performed according to standard cytogenetic methods using G-banding technique. RESULTS: Abnormal karyotype was found in 21 (9.50%) individuals. Of these 21 subjects, 4 (19.04%) exhibited sex chromosomal abnormalities and 17 (80.96%) had autosomal abnormalities. Male partners had significantly higher chromosomal abnormalities (5.88%) than of females (3.61%). These abnormalities were also higher in patients with recurrent spontaneous abortions than with IVF/ICSI failure (P < 0.05). CONCLUSIONS: These data may be indicative that chromosomal abnormalities are involved more in spontaneous abortions than in recurrent IVF/ICSI failure. Cytogenetic analysis could be valuable for these couples when clinical data fail to clarify the cause.
ABSTRACT
BACKGROUND: One of the frequent occurrences in chromosome rearrangements is pericentric inversion of the Chromosome 9; inv (9) (p11q12), which is consider to be the variant of normal karyotype. Although it seems not to correlate with abnormal phenotypes, there have been many controversial reports indicating that it may lead to abnormal clinical conditions such as infertility. The incidence is found to be about 1.98% in the general population. MATERIALS AND METHODS: We investigated the karyotypes of 300 infertile couples (600 individuals) being referred to our infertility clinic using standard GTG banding for karyotype preparation. RESULTS: The chromosomal analysis revealed a total of 15 (2.5%) inversions, among these, 14 male patients were inversion 9 carriers (4.69%) while one female patient was affected (0.33%). The incidence of inversion 9 in male patients is significantly higher than that of normal population and even than that of female patients (P< 0.05). CONCLUSIONS: This result suggests that inversion 9 may often cause infertility in men due to spermatogenic disturbances, which are arisen by the loops or acentric fragments formed in meiosis.
ABSTRACT
This study was desµgned to investµgate the effect of vitrification and post-thaw survival and chromosomal aberrations caused by vitrification of vitrified 8-cell mouse embryos in comparison with a controligroup. To this purpose the survival rate and the frequency of chromosomal aberrations were assessed in frozen-thawed 8-cell mouse embryos after various storage durations in the presence of ethyleneiglycol as cryoprotectant. eight-cell mouse embryos were obtained from NMRI mice 3 days after mating. Retrieved embryos were transferred to vitrification solution containing ethyleneiglycol as cryoprotectant, then transferred into a vitrification straw using standard technique, and vitrified in liquid nitrogen. Sixigroups of embryos according to storage duration (24 hours, 1 and 2 weeks, 1-6 months) were frozen. After appropriate storage periods embryos were thawed and studied for their viability 4-6 hours after thawing and intact embryos were transferred to fresh medium containing colcemid. After 48 hours, the embryos were fixed and studied for their chromosome abnormalities using Tarkowsky's drying technique. Results indicate that freezing affects the viability and chromosome structure of embryos when compared with the controligroup. Furthermore increasing the storage duration reduces the viability and increases the chromosome aberrations of embryos (such as aneuploidy and polyploidy). This result mµght indicate that the effects of vitrification on the cytoskeleton or other cellular organelle mµght produce chromosomal alterations leading to cell death.