The effects of male aging on semen quality, sperm DNA fragmentation and chromosomal abnormalities in an infertile population

Abstract

Purpose To investigate the effects of male aging on semen quality, DNA fragmentation and chromosomal abnormalities in the spermatozoa of infertile patients and fertile men. Methods Semen samples of 140 infertile patients (24-76 years) and 50 men with proven fertility (25-65 years) were analyzed according to WHO guidelines. DNA fragmentation was detected by TUNEL assay, while aneuploidy was assessed by FISH. Results In the patient group, semen volume and vitality of spermatozoa decreased significantly with age, while sperm concentration showed a statistically significant increase with age. DNA fragmentation as well as disomy of sex chromosomes and disomy 8 did not show a statistically significant change with age. However, the diploidy rate was significantly increased with patient's age. In the control group, conventional semen parameters as well as DNA fragmentation and chromosomal abnormalities did not show a statistically significant with age. Conclusion Increased age in infertile men is associated with an increase in sperm concentration and diploidy, as well as a decline in semen volume and sperm vitality. However motility, morphology and DNA fragmentation are not affected by male age.

Effects of reduced seminal enzymatic antioxidants on sperm DNA fragmentation and semen quality of Tunisian infertile men

“…Zini et al [39] demonstrated negative correlations between sperm DNA integrity and sperm quality in partners of couples attending IVF clinics. Additionally, in a small cohort of patients consulting for infertility investigation, prospective analyzes showed that both sperm motility and sperm morphology were inversely correlated to the rate of nuclear DNA fragmentation [10][11][12]36]. These results corroborated with our findings and suggested that sperm motility and morphology defects may be in part due to a reduction of sperm DNA integrity which can be promutagenic and can adversely affect fetal outcome after IVF and has lifelong implications on health of child [34].…”

“…In our study, no correlation was found between the age and the sperm DNA fragmentation. This was in agreement with the results of [15] who found no difference in DNA fragmentation rate according to age among 212 men aged between 25 and 70 years, but in disagreement with the results of others studies [10,11,35] who found a significant correlation between DNA fragmentation and patient's age.…”

“…Our data were in agreement with the observations of [25,39,40] who found that sperm DFI was significantly higher in Astheno and oligozoospermic patients than normozoospermics. Huang et al [22] and [10,11] evaluated also sperm DNA fragmentation in correlation with sperm parameters using TUNEL assay and they noted significant elevated levels in patients with sperm dysfunctions than in those with normal sperm criteria. Nevertheless, several other studies didn't corroborate with our findings and reported elevated rates of sperm DFI in normozoospermics compared to the abnormal groups [31].…”

“…Other factors which can induce sperm DNA fragmentation were cited like defective apoptosis before ejaculation ( [29], Brahem et al [11]), improper packaging and ligation during sperm maturation and the advanced age of infertile men [10,11]. Accordingly, these mechanisms, co-dependently with OS, might be responsible for sperm DNA fragmentation [34].…”

Effect of male age on the outcome of in vitro fertilization: oocyte donation as a model

“…The contribution of advancing female age to pregnancy outcomes is well documented, yet knowledge on effects of male age is much less [1,2]. Studies have shown that semen parameters, such as volume [3], total sperm count [4], sperm DNA integrity [3,5] and so on, would diminish with the increase of male age, which may undermine male fecundity. However, semen parameters are only indirect indicators of male fecundity and cannot reflect the effect of aging on male fecundity directly.…”