Risk factors for breast cancer in Turkish women with early pregnancies and long-lasting lactation - A case-control study

Kuru B., Ozaslan C., Ozdemir P., Dinc S.

ACTA ONCOLOGICA, vol.41, no.6, pp.556-561, 2002 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 41 Issue: 6
  • Publication Date: 2002
  • Doi Number: 10.1080/02841860214964
  • Journal Name: ACTA ONCOLOGICA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.556-561
  • Hacettepe University Affiliated: Yes


A hospital-based case-control study was carried out among 504 women with breast cancer and 610 controls to analyse the risk factors for breast cancer in Turkey. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each risk factor were obtained from logistic regression analysis. Risk factors for breast cancer were found to be long-term lactation (greater than or equal to5 years versus never OR 0.31, 95% CI 0.12-0.79), young age at menarche (<15 years versus &GE;15 OR 1.72, 95% CI 1.30-2.28), late age at first full-term pregnancy (&GE;30 versus <20 OR 2.86, 95% CI 1.32-6.21), oral contraceptive use ( ever versus never OR 1.51, 95% CI 1.10-2.08), positive family history (positive versus negative OR 2.81, 95% CI 1.35-5.82), and menstrual irregularity (yes versus no OR 1.61, 95% CI 1.05-2.49). The results of the present study will lead to a better understanding of the risk factors for breast cancer in a developing country.