Age at first birth, parity and risk of breast cancer: A meta‐analysis of 8 studies from the nordic countries

@article{Ewertz1990AgeAF,
  title={Age at first birth, parity and risk of breast cancer: A meta‐analysis of 8 studies from the nordic countries},
  author={Marianne Ewertz and Stephen W. Duffy and Hans-Olov Adami and Gunnar Kvåle and Eiliv Lund and Olav Meirik and Anders Mellemgaard and Irma Soini and Hrafn Tulinius},
  journal={International Journal of Cancer},
  year={1990},
  volume={46}
}
Several large epidemiological studies in the Nordic countries have failed to confirm an association between age at first birth and breast cancer independent of parity. To assess whether lack of power or heterogeneity between the countries could explain this, a meta‐analysis was performed of 8 population‐based studies (3 cohort and 5 case‐control) of breast cancer and reproductive variables in the Nordic countries, including a total of 5,568 cases. It confirmed that low parity and late age at… Expand
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TLDR
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