Reproductive factors and breast cancer risk in Iceland. A second cohort study
Abstract In a previous prospective study we showed elevated risks for breast cancer in nulliparous women compared to parous women, in those having their first pregnancy at a higher age, and those with few children. This was based on 216 women diagnosed with breast cancer during 1965 to 1975 among 34...
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crwiley:10.1002/ijc.2910460604 2024-06-02T08:09:05+00:00 Reproductive factors and breast cancer risk in Iceland. A second cohort study Tulinius, Hrafn Sigvaldason, Helgi Hrafnkelsson, Jón Ólafsdóttir, Guðriður Tryggvadóttir, Laufey Sigurðsson, Kristján 1990 http://dx.doi.org/10.1002/ijc.2910460604 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fijc.2910460604 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ijc.2910460604 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor International Journal of Cancer volume 46, issue 6, page 972-975 ISSN 0020-7136 1097-0215 journal-article 1990 crwiley https://doi.org/10.1002/ijc.2910460604 2024-05-03T10:54:33Z Abstract In a previous prospective study we showed elevated risks for breast cancer in nulliparous women compared to parous women, in those having their first pregnancy at a higher age, and those with few children. This was based on 216 women diagnosed with breast cancer during 1965 to 1975 among 34,525 women having attended the cervix cancer detection clinic in Iceland by the end of 1974, and born between 1906 and 1945. The present investigation on 848 cases, diagnosed among 6 1,040 women attending the cervix cancer detection clinic during 1964 to 1984 and born between 1901 and 1960, shows the same risk factors to be significant. The relative risks are, however, smaller. The reasons for the difference in relative risks are discussed, We find that the effect of age at first birth is significant for women up to the age of 65 and not for older women. In both cohorts, women older than 55 are underrepresented and more so in the earlier report. In addition, the small number of cases in the reference group with age at first birth below 20 appears to have made the figures of our earlier report unreliable. Article in Journal/Newspaper Iceland Wiley Online Library International Journal of Cancer 46 6 972 975 |
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Wiley Online Library |
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crwiley |
language |
English |
description |
Abstract In a previous prospective study we showed elevated risks for breast cancer in nulliparous women compared to parous women, in those having their first pregnancy at a higher age, and those with few children. This was based on 216 women diagnosed with breast cancer during 1965 to 1975 among 34,525 women having attended the cervix cancer detection clinic in Iceland by the end of 1974, and born between 1906 and 1945. The present investigation on 848 cases, diagnosed among 6 1,040 women attending the cervix cancer detection clinic during 1964 to 1984 and born between 1901 and 1960, shows the same risk factors to be significant. The relative risks are, however, smaller. The reasons for the difference in relative risks are discussed, We find that the effect of age at first birth is significant for women up to the age of 65 and not for older women. In both cohorts, women older than 55 are underrepresented and more so in the earlier report. In addition, the small number of cases in the reference group with age at first birth below 20 appears to have made the figures of our earlier report unreliable. |
format |
Article in Journal/Newspaper |
author |
Tulinius, Hrafn Sigvaldason, Helgi Hrafnkelsson, Jón Ólafsdóttir, Guðriður Tryggvadóttir, Laufey Sigurðsson, Kristján |
spellingShingle |
Tulinius, Hrafn Sigvaldason, Helgi Hrafnkelsson, Jón Ólafsdóttir, Guðriður Tryggvadóttir, Laufey Sigurðsson, Kristján Reproductive factors and breast cancer risk in Iceland. A second cohort study |
author_facet |
Tulinius, Hrafn Sigvaldason, Helgi Hrafnkelsson, Jón Ólafsdóttir, Guðriður Tryggvadóttir, Laufey Sigurðsson, Kristján |
author_sort |
Tulinius, Hrafn |
title |
Reproductive factors and breast cancer risk in Iceland. A second cohort study |
title_short |
Reproductive factors and breast cancer risk in Iceland. A second cohort study |
title_full |
Reproductive factors and breast cancer risk in Iceland. A second cohort study |
title_fullStr |
Reproductive factors and breast cancer risk in Iceland. A second cohort study |
title_full_unstemmed |
Reproductive factors and breast cancer risk in Iceland. A second cohort study |
title_sort |
reproductive factors and breast cancer risk in iceland. a second cohort study |
publisher |
Wiley |
publishDate |
1990 |
url |
http://dx.doi.org/10.1002/ijc.2910460604 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fijc.2910460604 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ijc.2910460604 |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
International Journal of Cancer volume 46, issue 6, page 972-975 ISSN 0020-7136 1097-0215 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/ijc.2910460604 |
container_title |
International Journal of Cancer |
container_volume |
46 |
container_issue |
6 |
container_start_page |
972 |
op_container_end_page |
975 |
_version_ |
1800754689731461120 |