Semen evaluation

Several factors may influence the results of semen evaluation, including the period of abstinence preceding collection of the sample, age, year of birth, season, social habits (e.g., alcohol, drugs, smoking) and health status (Jouannet et al., 1981 Auger et al., 1995 WHO,... 

Surveillance programmes also exist in occupational settings. In this case, it may be possible to follow reproductive histories (including menstrual cycles) or semen evaluations to monitor reproductive effects of exposure. With adequate exposure information, these could yield very useful data for risk assessment. Reproductive histories are easier and less costly to collect than semen evaluations. Semen studies also may have limited response rates, thus reducing their representativeness. It is important to reassure workers that the data they provide for such programmes remain confidential and will not affect their employment status (Samuels, 1988 Lemasters, 1993 Lindbohm, 1999). 

Not specified Imperial College of Science, Technology and Medicine Lead and male reproductive function, evaluate impact of changes in indicators of semen quality and reproductive hormones as function of occupational lead exposure ILZRO... 

One study directly evaluated semen and testicular endpoints in men consuming soy phytoestrogens. Mitchell et al. (2001) reported a study of 14 young men (18 to 35 years old) who consumed 40 mg per day of soy isoflavones (in a tablet form) for two months. The subjects were followed for two months before and three months after taking the supplement. The isoflavone supplement did not change testicular or ejaculate volume, or sperm concentration, count, or motility. 

Male patients hypophysectomized because of a pituitary tumor, who had normal semen counts despite undetectable serum gonadotropins after surgery, have been discovered to harbor constitutively active forms of the FSHR gene. Because the benign phenotype is only unmasked by the development of an unrelated tumor, the frequency of these mutations in the general population is difficult to evaluate (83,86). 

DNA Deoxyribonucleic acid is the repository of hereditary characteristics. The most commonly described form of DNA is the double-stranded form, arranged as a helix. Chromosomes are composed of double-stranded DNA. So called DNA fingerprinting offers a basis for evaluating the probability that blood, hair, semen or tissue samples originate from a given person, and thus offers a forensic tool as well as a means to determine lineages of humans and animals... 

Reports of studies with semen analyses have rarely included an evaluation of endocrine status (hormone levels in blood or urine) of exposed males (Adamopoulos et al., 1996 Larsen et al., 1999). Conversely, studies that have examined endocrine status typically do not have data on semen quality (McGregor Mason, 1990,1991 Egeland et al., 1994). Endocrine evaluation gives important information on reproductive organs. Estradiol, progesterone, testosterone, FSH, LH and prolactin are the hormones that are most informative. Inhibins and other more recently characterized factors may provide tools in the future. 

Williams, J., Gladen, B.C., Turner, T.W, Sclirader, S.M. Chapin, R.E. (1991) The effects of ethylene dibromide on semen quality and fertility in the rabbit evaluation of a model for human seminal characteristics. Fundam. appl. Toxicol.. 16, 687-700... 

G3. Gavella, M., Lipovac, V., Vucic, M., and Rocic, B., Evaluation of ascorbate and urate antioxidant capacity in human semen. Andrologia 29, 29-35 (1997). 

WHO has established protocols for the evaluation of semen quality (male fecundity) and infertile couples. 

Another question that needs to be considered is whether fertility studies conducted in nonhuman primates provide sufficient useful safety information for the patients to justify the use of the animals The one aspect of the nonhuman primate fertility studies that cannot accurately be assessed is fertility. Nonhuman primates have a naturally low fertility rate [37] and high spontaneous abortion rate [38] such that the number of animals that would be required to demonstrate a meaningful effect on fertility would be too large to be practical or ethical. Therefore the fertility studies in nonhuman primates focus on evaluation of hormone levels and semen analysis. This limited information provides minimal safety information over and above the standard toxicology endpoints, and therefore the value of conducting these studies should be carefully considered. 

The laboratory evaluation of male infertility is separated into three main components (1) the semen analysis, (2) endocrine parameters, and (3) immunological parameters. A basic approach to the diagnosis of male factor infertility is shown in Figure 53-15. 

Semen Analysis. The semen analysis measures ejaculate volume, pH, sperm count, motility, and forward progression. Semen should be analyzed within 1 hour after collection. Although the semen analysis is not a test for infertility, it is considered the most important laboratory test in the evaluation of male fertility. Controversy exists as to what constitutes a normal semen profile. With the exception of the azoospermic male (defined as no sperm in the ejaculate), the lines between fertility and infertility are blurred, and are intimately associated with the status of the female partner s reproductive function. However, clinical studies of infertile men and World Health Organization (WHO) guidelines have helped establish hmits of adequacy (Table 53-4). "... 

Harper, M.J.K. (1994). Gamete and gote transport, in The physiology of Reproduction (E. Knobil and J.D. NerU, eds.), pp. 123-187. Raven Press, New York. Hong, C.Y., Chao, H.T., Tsai, K.L. and Ng, H.T. (1991). Evaluation of human sperm motflity by means of transmembrane migration method and computer-assisted semen analysis—a comparison study. Andrologia 23, 7-10. 

The most common semen abnormality in patients with varicocele and infertility is poor sperm motility, followed by abnormal morphology, and then depression of sperm count. The isolated finding of abnormal sperm motility has been referred to as a stress pattern. The normal World Health Organization (WHO) values [13] for the commonly evaluated parameters studied during semen analysis include the following ... 

The two parameters that are usually evaluated in the assessment of the dinical efficacy of the treatment are semen analysis changes and the pregnancy rate. 

Zrimsek, R Kune, J. Kosec, M. Mrkun, J. Spectrophotometric application of resazurin reduction assay to evaluate boar semen quality. Int. J. Androl. 2004,27, 57-62. 

A. Semen analysis The following information excerpted from the document Evaluation of Testicular Function , submitted by the Corporate Medical Department of the Shell Oil Company (e) ibit 39-3), may be useful to physicians conducting the medical surveillance program ... 

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