Cancer Causes & Control

, Volume 21, Issue 3, pp 393–397 | Cite as

Breastfeeding reduces breast cancer risk: a case–control study in Tunisia

  • Msolly Awatef
  • Gharbi Olfa
  • Harrabi Imed
  • Mahmoudi Kacem
  • Chabchoub Imen
  • Chafai Rim
  • Bibi Mohamed
  • Ben Ahmed Slim
Original paper


In this report, we examined the relationship between mother’s breastfeeding history and her risk of breast cancer, in a case–control study in Tunisia between 2006 and 2009. About 400 breast cancer cases and 400 controls were included. Cases and controls were interviewed using a standardized structured questionnaire to obtain information on breastfeeding and other risk factors. Mean duration of breastfeeding per child was significantly associated with a reduced risk of breast cancer for women who breastfed for >24 months per child. The OR was 0.46 (95% CI, 0.28–0.76) when compared those who breastfed for <6 months. The test for trend was significant (p = 0.01). A significantly reduced risk of breast cancer was found for those whose lifetime duration of breastfeeding was 73–108 months (OR = 0.65, 95% CI, 0.36–1.18) and for those who breastfed for ≥109 months (OR = 0.42, 95% CI, 0.20–0.84). Stratification by menopausal status showed a reduced risk of breast cancer associated with a longer duration of breastfeeding for both pre- and postmenopausal women. The risk reduction was more consistent for lifetime duration of breastfeeding, the test for trend being significant for both pre- (p = 0.03) and postmenopausal (p = 0.01) women. These results support an inverse association between breastfeeding and breast cancer risk.


Breast cancer Breastfeeding Case–control study 



This work was supported by the research unit “oncogénétique clinique” University of Medicine of Sousse. We would like to thank Mrs Kassab Asma for English revision.


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Msolly Awatef
    • 1
  • Gharbi Olfa
    • 1
  • Harrabi Imed
    • 2
  • Mahmoudi Kacem
    • 1
  • Chabchoub Imen
    • 1
  • Chafai Rim
    • 1
  • Bibi Mohamed
    • 1
  • Ben Ahmed Slim
    • 1
  1. 1.Department of Medical OncologyCHU Farhat HachedSousseTunisia
  2. 2.Department of EpidemiologyCHU Farhat HachedSousseTunisia

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