Gonyostmum semen is a freshwater raphidophyte that has increased in occurrence and abundance in several countries in northern Europe since the 1980s. More recently, the species has expanded rapidly also in north-eastern Europe, and it is frequently referred to as invasive. To better understand the species history, we have explored the phylogeography of G. semen using strains from northern Europ...

This study characterized seasonal changes in circulating LH and testosterone and in semen production and quality in the Northern pintail duck. Plasma LH and testosterone were measured in blood samples collected weekly throughout the year from eight males exposed to natural fluctuations in day length and temperature. Semen quality was evaluated weekly in these same males from April-June, the mon...

Background. Infertility is both a clinical and a public problem, affecting the life of the couple, the healthcare services, and social environment. Standard semen analysis is the surrogate measure of male fertility in clinical practice. Objective. To provide information about the relationship between semen parameters and spontaneous conception. Methods. We evaluated retrospectively 453 pregnanc...

BACKGROUND Standardization of the semen analysis may improve reproducibility. We assessed variability between laboratories in semen analyses and evaluated whether a transformation using Z scores and regression statistics was able to reduce this variability. MATERIALS AND METHODS We performed a retrospective cohort study. We calculated between-laboratory coefficients of variation (CVB) for spe...

PURPOSE To investigate whether the semen quality of men undergoing conventional semen analysis is deteriorating over time. MATERIALS AND METHODS We analyzed and compared the sperm count, motility and morphology of 2300 semen samples provided by males undergoing conventional seminal analysis, from years 2000 to 2002 and 2010 to 2012. The incidences of severe oligozoospermia and azoospermia ove...

BACKGROUND Population-based study of semen quality is rare in literature. METHODS Healthy men aged 20-60 years from six Chinese provinces were invited to participate in the study between December 2000 and November 2002. Posters were distributed in the participating counties to enroll 200 subjects from each province. Medians, percentiles, and proportions below lower threshold of the WHO criter...

This article explores in detail the issue of the alleged decline in semen quality. The impetus for a comprehensive re-evaluation at this time is threefold: (1) the potential impact of a real decline in semen quality and subsequent human fertility is a priori critical to human welfare; (2) governments have begun to enact "anti-endocrine disruptor" legislation that is based, in part, on selected ...

The possible hazards of occupational exposure on the reproductive health of workers is of great interest. In this review, epidemiological study designs suitable for reproductive studies and sources of outcome and exposure data are described with a few examples. Studies have been conducted on hormonal changes, semen quality, fertility, and various outcomes of pregnancy, e.g., spontaneous abortio...

Chiu and her colleagues from Harvard School of Public Health and Massachusetts General Hospital present important new data on semen quality in relation to dietary pesticide exposure via fruit and vegetable intake (Chiu et al., 2015). To examine this relationship the authors utilized a novel approach that classifies fruits and vegetables into high versus low-to-moderate pesticide residue groups ...

Varicocele is a common condition worldwide but it is more prevalent in K.S.A. The aim of this study was to examine the effect of varicocelectomy on the fertility profile of affected men. A total of 75 men aged 12 – 70 years were diagnosed with varicocele during a period from July 2005 to September 2008. This included 67 Saudi and 8 non – Saudi patients. Sixty eight (90.66%) patients were adults...