Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1987-12-21
pubmed:abstractText
We investigated estrogen (estrone and estradiol) levels in serum and in nipple aspirates of breast fluid in relation to reproductive and menopausal characteristics in 104 normal women. In general, breast fluid and serum estrogen levels were not correlated and breast fluid estrogen levels were approximately 5 to 45 times higher than serum levels. Serum estrogen levels were lower in post-menopausal than in pre-menopausal women. In contrast, breast fluid estrogen levels were approximately the same in pre- and post-menopausal women. Breast fluid estrogen mean levels were lower in pre-menopausal parous women than in nulligravidous or nulliparous women whereas serum estrogen levels did not differ in these 3 groups. Breast fluid estrogen levels were positively correlated with months since last birth or since last breast-feeding. Estrogen levels were low in nipple aspirates of breast milk but gradually increased in breast fluid of non-lactating women over a period of several years after cessation of lactation. Serum estrogen levels did not increase with months since last breast-feeding. We were unable to evaluate the post-partum effect of pregnancy without lactation due to the small numbers of these subjects. The high concentrations of estrogen in breast fluid and the absence of a relationship to serum estrogen levels may explain why prior serum studies have failed to link variations in serum estrogens with breast cancer risk. The prolonged low levels of breast fluid estrogens following full-term birth and lactation may, in part, provide a mechanism by which parity reduces breast cancer risk.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0020-7136
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
587-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Influence of pregnancy and lactation on serum and breast fluid estrogen levels: implications for breast cancer risk.
pubmed:affiliation
Department of Epidemiology and International Health, University of California, San Francisco 94143.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.