Study of a group of 484 fertile men Part I: Distribution of semen characteristics

Abstract

The semen characteristics studied were the sperm count, semen volume, morphology and pre-freeze and post-thaw motility. Two categories of fertile men were investigated: semen donor candidates for artificial insemination and pre-vasectomy subjects. Since mean values for each variable in the two series were similar, they could be considered as a single group of 484 fertile men. Only those subjects whose ejaculates were obtained after an abstinence of 5 days or less were retained. The distribution, mean and percentiles were determined for each variable. The 10th and 90th percentiles for sperm count, percentage of motile forms and percentage of normal cells were respectively 25 and 180 million per ml, 60% and 80% and 50% ad 75%. The three variables, sperm count, semen volume and total number of spermatozoa which were dependent on abstinence were analysed in the same manner for 3 days of abstinence. The group studied seemed to be as representative and as well defined as possible.

Is there really a decrease in sperm parameters among healthy young men? A survey of sperm donations during 15 years

“…The semen donors were all in good physical health, confirmed by medical history, physical examination, and blood tests. The donors were within the narrow age range of 20 to 30 years and the duration of abstinence was short (3 to 4 days), thus eliminating the main reported confounding factors (17,18). Moreover, assay methods and equipment during the study period were consistent and all the examinations were done by the same technician.…”

Influence of ejaculation frequency on semen characteristics in chimpanzees (Pan troglodytes)

“…The animals had the opportunity to copulate and/or to masturbate freely. The large intra-individual variations of semen values observed may be related in part to the sexual abstinence period, as in man (Schwartz et al, 1979;Jouannet et al, 1981).…”

Macleod Revisited: Sperm Count Distributions in 374 Fertile Men From 1971 to 1994

“…Both parameters have been shown in previously published reports to have effects on sperm counts. 8,9 Whereas we do have data on duration of abstinence and age for each man in the contemporary cohort, and have used this data to correct sperm counts for differences in these parameters in our other publications, no such data are available in the MacLeod and Gold 7 study.…”