Eberhard Nieschlag

External quality control in the andrology laboratory: an experimental multicenter trial *

An external quality control study for semen analysis was performed involving 10 andrology laboratories in geographically separate locations. For the evaluation of sperm concentration, eight samples with different concentrations, and for the assessment of sperm morphology three slides prepared from different semen samples were distributed. Sperm motility was evaluated in five samples delivered cryopreserved to the participants. The coefficients of variation (CVs) for sperm counts varied with the sperm concentrations showing highest variability for low and lowest for high concentrations (range 23% to 73%). The CV for sperm morphology ranged from 25% for normal heads to 87% for abnormal midpieces. The CV for motility of sperm was 21%. For comparison the mean CVs for internal quality control were as follows: 10% for concentration, 8% for morphology (normal heads), and 8% for motility.

Internal quality control of semen analysis

OBJECTIVEnTo test a scheme for quality control of semen analysis.nnnDESIGNnThe reproducibility of assessment of sperm concentration, motility, and morphology was obtained for the same sample measured by different technicians (between or intertechnician variation) and for different samples assessed by each technician with time (within or intratechnician variation).nnnSETTINGnAndrology Laboratory.nnnPATIENTSnSemen samples were analyzed from all patients attending the clinic.nnnINTERVENTIONSnNone.nnnMAIN OUTCOME MEASURESnWithin technician and between technician coefficients of variation for concentration, motility, and morphology.nnnRESULTSnWhen 100 sperm were routinely assessed, both intratechnician variation, as assessed from the precision of duplicate measurements, and intertechnician variation revealed hyperbolic curves with increasing variation at low percentages (less than 20) of motile or morphological forms. When these low values were excluded, mean intratechnician variations were 5.0%, 8.4%, and 2.8% for concentration, motility, and morphology, respectively, and mean intertechnician variations were, respectively, 6.1%, 5.6%, and 5.6%. Similar mean intertechnician variation for morphology was obtained for repeated assessment of prestained (7.3%) or presmeared (5.9%) slides. The use of cryopreserved semen to monitor longitudinal changes in the technicians assessments revealed variations of 8.1% to 12% in concentration and 9.7% to 14% in motility. Computing the monthly means for sperm concentration, motility, and morphology over a 4.5-year period revealed a marked reduction in percentage of normal morphological forms, unrelated to the sperm count or mean age of the men attending the clinic. This was shown to be a result of a shift in the assessment by technicians.nnnCONCLUSIONSnQuality control is necessary and possible in an andrology clinic.

A technique for standardization and quality control of subjective sperm motility assessments in semen analysis

OBJECTIVEnTo establish a quality control method to monitor and eventually to standardize the subjective assessment of sperm motility in conventional semen analysis.nnnDESIGNnQuality control study running over 2 years.nnnSETTINGnUniversity infertility clinic and andrology laboratory.nnnPATIENT(S)nRandomly chosen patients attending the clinic.nnnMAIN OUTCOME MEASURE(S)nConventional semen analysis with sperm motility assessed by grading according to the World Health Organization (WHO) criteria and analysis of individual sperm tracks with a computer-aided sperm analysis (CASA) system. Formulas were established to identify, from the track data, the threshold velocity values for distinguishing between motility grades a and b and motility grades b and c for each technician.nnnRESULT(S)nThe subjective thresholds above which technicians categorized sperm as WHO grades a and b were determined by CASA to be 61 +/- 1 and 11 +/- 1 micron/s (straight-line velocity), respectively. Agreement among three to five technicians over 2 years was reasonable (coefficient of variation < 20%), but threshold values were variable.nnnCONCLUSION(S)nAgreement within and between laboratories in the assessment of sperm motility grades could be achieved by agreeing on designated values for threshold velocities for grade a and b sperm. On the basis of such values, CASA analysis could be used to provide the expected percentages of grades a, b, and c forms for quality control samples recorded and distributed on videotapes, against which technicians could adjust their subjective assessments.

Comparative pharmacokinetics of androgen preparations: Application of computer analysis and simulation

In replacing an endogenous hormone a safe general principle appears to be to mimic, as closely as possible, the normal concentrations of that hormone or its active metabolites (Cantrill et al. 1984). Following this principle testosterone treatment of male hypogonadism should avoid unphysiologically high testosterone serum concentrations to prevent possible side-effects or low concentrations to prevent androgen deficiency.

Hormonal Male Contraception: A Real Chance?

Health and prosperity of individuals and communities alike are linked to population growth. European and North American countries are now in the late phase of a demographic transition and have achieved largely stable populations where birth rates equal or only slightly exceed death rates. This balance depends to a paramount extent on the availability of methods for birth control. This is illustrated by representative opinion polls performed in Germany 1958 and in 1989 (Allensbach 1958 and 1989). At both time points the ideal family size, in the opinion of the majority of couples of reproductive age, comprised two children.

Male Hormonal Contraception: Love's Labour's Lost?

Although a large proportion of clinical research is driven by the pharmaceutical industry in the case of male contraception industry fails. Without the long-range perspective and endurance of institutions and organizations such as the National Institute of Child Health and Human Development CONRAD Population Council WHO some medical research councils and a few foundations male contraception would long ago have been abandoned. The principle and effectiveness of hormonal male contraception has been demonstrated in many studies crowned by the most recent trial in the current issue of the Journal of Clinical Endocrinology and Metabolism. The fact that the majority of clinical trials on hormonal male contraception have been published in this journal emphasizes the high priority the scientific community attributes to these endeavors. Little more is required to convince industry to bring this development to fruition. Comparing the situation with the development of the female pill the lack of public advocacy for male contraception is striking. Male contraception lacks prominent advocates whereas the development of female contraception benefited from personalities such as Margaret Sanger (1879-1966) and Katherine McCormick (1875-1967). Were Arnold Schwarzenegger or Barack Obama to advocate male contraception it would become a marketable entity in no time! (excerpt)

Evaluation of the semi-automated Autosperm semen analysis system. I. Accuracy and comparison with the conventional method and the automated Hamilton-Thorn system.

The accuracy of measurements by the semi-automated Autosperm (Amsaten N.V.S.A. Corp., DePinte, Belgium) semen analysis system was assessed by recounting and manually tracking sperm recorded on videotape during analysis of 51 ejaculates. Mean inaccuracies in the analysis of sperm concentration and percentage motility were 15% and 22%, respectively. Measurements of sperm movement characteristics relied on the skill of the operator and discrepancies (means around 10%, maximum 57% to 184%) depended on the straightness of sperm paths. Although less expensive than the fully automated system, semen analysis by Autosperm is a subjective and labor-intensive method. Furthermore in comparison, data obtained using Autosperm also provide less information, and agreements of matched data with those obtained by the conventional methods were not significantly better.