Semen analysis

About: Semen analysis is a research topic. Over the lifetime, 4909 publications have been published within this topic receiving 143225 citations.

Poor quality of sperm as it affects repeated early pregnancy loss.

Abstract: A study was carried out to determine whether males contribute to repeated early pregnancy loss. Semen samples were analyzed from proven-fertile men (n = 51 group I) and from men whose partners presented with early pregnancy loss (>3 first trimester abortions, n = 32 group II). Routine analysis, sperm function tests, and ultrastructural studies of sperms were carried out. Female factor could be identified in 25 (78%) couples, and in 7 (22%) no cause either male or female could be identified and the semen analysis was normal. Percent morphologically normal did not differ significantly between the groups, but increased sperm head abnormalities were seen. The functional tests were all normal except for a significant decrease in the capacity of nuclear chromatin to decondense in vitro. The ultrastructural studies showed defects of chromatin condensation and irregular nuclei with vacuoles. This study points to the loss of chromatin integrity as a possible contributing factor from males to early pregnancy loss.

The relationship between sperm viability and DNA fragmentation rates

Abstract: In humans, sperm DNA fragmentation rates have been correlated with sperm viability rates. Reduced sperm viability is associated with high sperm DNA fragmentation, while conversely high sperm viability is associated with low rates of sperm DNA fragmentation. Both elevated DNA fragmentation rates and poor viability are correlated with impaired male fertility, with a DNA fragmentation rate of > 30% indicating subfertility. We postulated that in some men, the sperm viability assay could predict the sperm DNA fragmentation rates. This in turn could reduce the need for sperm DNA fragmentation assay testing, simplifying the infertility investigation and saving money for infertile couples. All men having semen analyses with both viability and DNA fragmentation testing were identified via a prospectively collected database. Viability was measured by eosin-nigrosin assay. DNA fragmentation was measured using the sperm chromosome structure assay. The relationship between DNA fragmentation and viability was assessed using Pearson’s correlation coefficient. From 2008-2013, 3049 semen analyses had both viability and DNA fragmentation testing. A strong inverse relationship was seen between sperm viability and DNA fragmentation rates, with r = -0.83. If viability was ≤ 50% (n = 301) then DNA fragmentation was ≥ 30% for 95% of the samples. If viability was ≥ 75% (n = 1736), then the DNA fragmentation was ≤ 30% for 95% of the patients. Sperm viability correlates strongly with DNA fragmentation rates. In men with high levels of sperm viability ≥ 75%, or low levels of sperm viability ≤ 30%, DFI testing may be not be routinely necessary. Given that DNA fragmentation testing is substantially more expensive than vitality testing, this may represent a valuable cost-saving measure for couples undergoing a fertility evaluation.

Environmental exposure to non-persistent endocrine disrupting chemicals and semen quality: An overview of the current epidemiological evidence

Abstract: Some of the recent publications have reported a decline in semen quality in the last few decades. This phenomenon is associated with environmental factors, particularly with exposure to endocrine disrupting chemicals (EDCs). The aim of this publication is to critically review the literature on exposure to the following 6 ubiquitous environmental non-persistent EDCs: bisphenol A, triclosan, parabens, synthetic pyrethroids, organophosphate pesticides and phthalates, and on their influence on semen quality measured as sperm concentration, sperm volume, total sperm count, motility, total motile count, morphology, sperm motion, sperm DNA damage (comet extent, tail length, tail distributed moment, percent of DNA located in the tail (tail%), DNA fragmentation index, high DNA stainability, X:Y ratio and aneuploidy. Several electronic databases were systematically searched until 31 August 2016. Studies were qualified for the review if they: linked environmental exposure to non-persistent EDCs to semen quality outcomes, were published in English after 2006 (and, in the case of phthalates, if they were published after 2009) and were conducted in the case of humans. Out of the 970 references, 45 articles were included in the review. This review adds to the body of evidence that exposure to non-persistent EDCs may affect semen quality parameters and decrease semen quality. Int J Occup Med Environ Health 2018;31(4):377–414