Purpose To investigate the effects of male aging on sperm quality and sperm DNA fragmentation. Methods The ejaculates of 320 unselected men attending a fertility clinic and, as a control, 84 normozoospermic men without any history of ART were analyzed according to WHO guidelines. Sperm DNA fragmentation was measured by flow cytometry after staining with propidiumiodide. Results The patients were divided into four groups: <30 years, 30-35 years, 36-39 years and ≥40 years. Sperm motility decreased with increasing age whereas sperm concentration, morphology, and DNA fragmentation fluctuated throughout the four groups both among patients and among controls. However, we could not detect any significant correlation between male age and conventional semen parameters or sperm DNA fragmentation, respectively, neither in the patients' group nor among the controls. This also applies to a classification of patients and controls into only two age groups with a cut-off point at 35 years. Conclusions Our findings suggest that neither the routinely assessed semen parameters nor the amount of spermatozoa with fragmented DNA are affected by male age.

Two hundred and sixty-five unfertilized human metaphase II (M II) oocytes from an in vitro fertilization program were studied cytogenetically using our chromosomal technique, a gradual fixation-air drying method. Of the 265 oocytes, 185 (70%) were successfully karyotyped. There were 21 aneuploids (11.4%) consisting of 8 hyperhaploids (4.3%), 11 hypohaploids (5.9%) and 2 complex cases (1.1%). There were also 9 structural anomalies (4.9%) and 18 diploids (9.7%). In aneuploidy, the loss or gain of dyads (so-called nondisjunction) occurred more frequently than the loss or gain of monads (so-called predivision). The frequency of abnormally behaved chromosomes (segregation errors) due to nondisjunction, anaphase lag and predivision was studied among the seven chromosomal groups (A-G) and compared with the frequency expected from an equal probability of segregation errors in each of the 23 chromosomes. The observed frequency was somewhat higher than the expected frequency in groups E and G but the difference was not statistically significant in either group. These results were discussed in relation to previous studies on human M II oocyte chromosomes.

No abstract

No abstract

The data suggest that giant oocytes may play an important, yet underestimated role in causing digynic triploidy. We recommend the exclusion of giant oocytes from IVF trials and that giant cells should be discarded, even if they carry the regular number of two pronuclei.