Evaluación de parámetros seminales no convencionales en individuos cuyas parejas presentan muerte embrionaria temprana recurrente: en busca de un valor de referencia

Influence of ejaculation frequency on seminal parameters

BACKGROUND

Several factors have been shown to influence semen parameters, one of which is sexual abstinence; a clinical criteria included in the semen evaluation to provide maximum sperm quality. The aim of the present study was to assess the effect of a daily ejaculation frequency on conventional and functional semen parameters.

METHODS

Semen samples were collected daily over a period of two weeks of which every second sample per person was processed and analyzed according to the World Health Organization guidelines. Furthermore, mitochondrial function, intracellular reactive oxygen species production and sperm DNA fragmentation were evaluated by flow cytometry.

RESULTS

Total sperm count and seminal volume per ejaculation declined and remained decreased for the duration of the daily ejaculation period. However, conventional parameters such as sperm concentration, motility, progressive motility, morphology, vitality and functional parameters such as sperm plasma membrane integrity, mitochondrial membrane potential and DNA fragmentation was not significantly affected and remained similar to the initial measurement throughout the daily ejaculation period. Despite intra- and inter individual variations, the average values of the basic semen parameters remained above the WHO (2010) reference values throughout the daily ejaculation period. Interestingly, a decreasing trend in intracellular ROS production was observed, although statistically not significant.

CONCLUSIONS

The study shows that an extended 2 week period of daily ejaculation does not have major clinical effects on conventional and functional seminal parameters.

[Evaluation of sperm functional parameters in normozoospermic infertile individuals]

OBJECTIVE

This study evaluated the integrity of the chromatin structure, reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), DNA damage and lipid peroxidation of semen samples from infertile men classified as unexplained infertility.

METHODS

Between February 2010 and July 2011 semen parameters and functional tests were evaluated in 10 subjects with proven fertility, 10 that belong to general population and 8 with idiopathic infertility. In addition to the conventional semen analysis, the following unconventional seminal analysis were conducted: evaluation of ROS, MMP, sperm chromatin structure assay (SCSA) by flow cytometry, assessment of sperm membrane lipid peroxidation by spectrophotometry, and alkaline comet assay by electrophoresis.

RESULTS

We observed a significant increase (P<.05) in the production of ROS and the fragmentation or sperm DNA damage in the population of infertile men. There were no statistically significant differences (P>.05) in the analysis of sperm membrane integrity between the groups. Moreover, we observed significant correlations (P<.05) between SCSA and comet assay (r=0.86) and the production of intracellular ROS (r=-0.588).

CONCLUSION

The sperm from individuals with idiopathic infertility showed high levels of intracellular ROS and increased levels of DNA fragmentation in the sperm. These results suggest that these two parameters are related to unexplained infertility and therefore have clinical importance as a possible diagnostic and prognostic tool in the evaluation of idiopathic male infertility.