The debate concerning the possible degradation in human sperm quality began in the 1970s, was revived at the beginning of the 1990s and has continued to mobilize the scientific community ever since. After the meta-analysis by Carlsen et al. (1992) showing a decline in human semen quality over the last 50 years, several groups investigated the sperm characteristics of more or less homogeneous gr...

Semen quality is a key indicator of the male reproductive ability. The decline in semen quality has been debated for several decades. However, data on decline in semen quality might be inconsistent given factors such as geographical area, ethnicity, environmental exposure and lifestyle changes. This study aimed to provide information on the semen quality of men in Northern Taiwanese. We recruit...

BACKGROUND ICSI is used increasingly often compared with standard IVF. The aim of the present study was to analyse the changes in the use of ICSI, and discuss possible causes and consequences. METHODS Data from National and Regional registers were analysed for trends in the use of ICSI and indications for assisted reproductive technology (ART). RESULTS The use of ICSI increased from 39.6% o...

BACKGROUND Timed and frequent intercourse around the time of female ovulation is recommended to improve conception. Although a significant number of articles have examined how the length of abstinence affects these semen analysis, the effects of frequent (daily) ejaculation has not been rigorously studied. METHODS Twenty normal men were recruited for daily ejaculation over 14 consecutive days...

BACKGROUND Although the effect of maternal age on fertility is well known, it is unclear whether paternal age also affects fertility. This cross-sectional study sought to characterize the association between age and semen quality, a well-known proxy of fertility status. METHODS A convenience sample of 97 non-smoking men (aged 22-80 years) without known fertility problems was recruited from a ...

A consensus exists that the basic semen analysis is the most important tool in male fertility investigation. In the last two decades, researchers and clinicians alike have relied on the World Health Organization (WHO) criteria for the interpretation of basic semen analysis. Nevertheless, the criteria for what constitutes a normal semen analysis remain controversial. Although a single test such ...

The clinical definition of male infertility is the presence of abnormal semen parameters in the male partner of a couple who have been unable to conceive after 1 year of unprotected intercourse (Dohle 2010). The World Health Organization defines male factor infertility as the presence of one or more abnormalities in the semen analysis, or the presence of inadequate sexual or ejaculatory functio...

BACKGROUND Although the depth of the counting chamber is an important factor influencing sperm counting, no research has yet been reported on the measurement and comparison of the depth of the chamber. We measured the exact depths of six kinds of sperm counting chambers and evaluated their accuracy. MATERIALS AND METHODS In this prospective study, the depths of six kinds of sperm counting cha...

The fifth edition of the World Health Organization (WHO) manual for semen analysis includes for the first time reference values for human semen characteristics. This paper considers whether such values will help to resolve the intensely debated data indicating temporal and geographical shifts in sperm counts and hypotheses that anthropogenic activities that result in the release of chemicals in...

PURPOSE The purpose of the study was to observe the effects of fenvalerate exposure on the semen quality of occupational workers. MATERIALS AND METHODS Thirty-two male workers who were exposed to fenvalerate and 46 male administrators in the office in the same pesticide factory were selected as the exposure group and internal control group, respectively, and 22 male administrators in a center...