Factors of reproductive risk in patients with breast cancer

Abstract

Introduction: Breast cancer is common in women and is the leading cause of cancer death worldwide. Objective: To identify risk factors for breast cancer in a group of 300 diagnosed patients and an equal number of controls at the "Institute of Oncology and Radiobiology of Cuba" from March / 2006 to December / 2009. Methods: An epidemiological and observational case - control study was carried out at the National Institute of Oncology and Radiobiology of Cuba, in the period from March 2006 to December 2009. A survey was carried out for the collection of the information. The universe consisted of 300 patients with breast cancer and 300 controls. We studied variables such as: age of onset of menarche, menstrual cycles, menopausal status, age of menopause, number of pregnancies, parity, age of first calving, time of accumulated lactation. Results: Were risk factors: The number of pregnancies from the third (OR: 0.74, 95% CI: 0.57-0.98), parity from the third birth (OR: 0.5; 95% CI: 0.27-0.96,  irregular menses (OR: 3.62, 95% CI: 2.22-5.9), late age at menopause (OR: 1.7 , 95% CI: 1.15-2.54) and the accumulated breastfeeding time less than 5 months (OR: 1.57; 95% CI: 1.09-2.63). Conclusions: Risk factors for breast cancer in the study population were irregular menses, late age at menopause, cumulative breast-feeding time of less than 5 months.