Study of aneuploidy and DNA fragmentation in gametes of patients with severe teratozoospermia.

This study investigated meiotic segregation in spermatozoa to determine if severe teratozoospermia should prevent the use of intracytoplasmic sperm injection (ICSI) because of the high production of gametes with chromosomal aneuploidies and analysed DNA fragmentation in gametes from the same semen to determine if DNA integrity was worse in patients with severe teratozoospermia. Sperm samples from 12 infertile patients were studied by fluorescence in-situ hybridization for chromosomes X, Y, 13, 18 and 21 and by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling. Four patients with a majority of macrocephalic forms with multiple flagella had more than 99% spermatozoa with abnormal chromosomal content. The other patients (globozoospermia or other abnormalities concerning sperm heads) had no increased aneuploidy or a slightly significant increase (P<0.05). The rate of DNA fragmentation was significantly higher in infertile patients than in the controls (P<0.001; 14.3% versus 1.20%, respectively) but presented important variability. Therefore, ICSI should not be attempted if men have macrocephalic gametes with multiple flagella but morphology is not always a good predictor of chromosomal content, depending upon the kind of teratozoospermia. Evaluation of the rate of aneuploidy and DNA fragmentation in gametes of patients with severe teratozoospermia is recommended.