Semen analysis performed by different laboratory teams: an intervariation study

Abstract

Some recent studies have indicated that sperm concentration has decreased during the last 50 years. However, comparisons between laboratories have revealed that geographical differences seem to exist and that any decrease may not be global. One point of criticism concerning comparison of results from different laboratories has been that some of the discrepancies detected could reflect the lack of standardized methods used in the different laboratories. Four teams, each consisting of one physician and one technician from groups which have recently published data on semen quality, met in order to evaluate the variability between their laboratories on semen analysis. Twenty-six fresh semen samples from unselected men were analysed. The groups analysed the samples according to the normal practice in their laboratories, using their own equipment. The variation between laboratories was estimated through a random effects model. For sperm concentration and semen volume assessment a remarkable consistency between laboratories was detected, in contrast to the very considerable inter-individual variation. For sperm motility and morphology assessments interlaboratory consistency was much poorer. In conclusion, evaluation of sperm motility and morphology characteristics requires further standardization in order to achieve comparable data from different laboratories. However, semen volume and sperm concentration are characteristics which can be compared reliably between laboratories, when similar methodologies are used.

Semen quality among Danish and Finnish men attempting to conceive. The Danish First Pregnancy Planner Study Team

“…In an evaluation study (15), the inter-laboratory variation in sperm count was around 15%. However, significant inter-individual differences were found and may hamper the interpretation of the morphology data.…”

“…In a previously performed evaluation study, technicians from different European countries (including Denmark and Finland) analysed the same 26 semen samples (15). The inter-laboratory variation in sperm count was tested and no systematic difference was found (inter-laboratory coefficient 0.96, paired t-test = 0.23, P = 0.82).…”

Prostate-specific antigen as a biomarker of condom failure: comparison of three laboratory assays and self-reported condom use problems in a randomized trial of female condom performance

“…While this study was not designed to meet biological thresholds for conception or sexually transmitted infection (STI), it is important to note that processed semen samples containing fewer than 10×10 6 spermatozoa are unlikely to result in fertilization [17]. Since the median sperm count in fertile men ranges between 70×10 6 /mL and 100×10 6 /mL [18,19], exposure to a volume of ejaculate <0.1 mL is not likely to result in conception. After inoculation of 0.1 mL of semen, the median vaginal PSA is 273 ng/mL (Appendix Table A1).…”

CASA derived human sperm abnormalities: correlation with chromatin packing and DNA fragmentation

“…Various morphological abnormalities of sperm head and morphometric parameters are often associated with infertility and to a large extent influence the fertilization cates and pregnancy outcome [2][3][4]. Traditionally, these parameters were routinely evaluated by light microscopy, but the drawbacks of this methodology such as subjectivity and high interobserver variability makes interpretation unreliable [5]. With the introduction of CASA (computer assisted semen analysis) assessment of the morphometric and morphological characteristics of spermatozoa is now more accurate, which until now was not possible by routine light microscopic analysis [6,7].…”