Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2004-9-9
pubmed:abstractText
Seasonal, daylight-dependent variation in human spermatozoa counts, with lowest values during summer, has been suggested. To test this hypothesis, we performed a longitudinal study of semen quality and reproductive hormone levels in Norwegian men living north and south of the Arctic Circle. An ejaculate and a serum specimen were obtained both in summer and in winter from 92 volunteers in Tromsoe (69 degrees north latitude) and 112 in Oslo (60 degrees north latitude). Semen analyses were performed, and serum was assayed for FSH and inhibin B. The median spermatozoa concentration in Tromsoe after adjustment for abstinence period length was 49 x 10(6)/ml in summer and 54 x 10(6)/ml in winter. Corresponding values for Oslo were 59 x 10(6)/ml and 54 x 10(6)/ml. The seasonal differences in spermatozoa concentration were not statistically significant, nor were significant differences observed in median total spermatozoa count, semen volume, percentage progressive motile spermatozoa, or FSH. In Tromsoe, but not Oslo, inhibin B concentration was slightly, but significantly (P = 0.02) higher in winter than summer (229 ng/liter vs. 223 ng/liter). The length of the daylight period may have a slight impact on hormonal markers of spermatogenesis but does not cause substantial changes in spermatozoa numbers and motility.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-972X
pubmed:author
pubmed:issnType
Print
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4397-402
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Reproductive function during summer and winter in Norwegian men living north and south of the Arctic circle.
pubmed:affiliation
Fertility Center, Scanian Andrology Centre, Malmö University Hospital, SE 205 02, Malmö, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't