ABSTRACT
OBJECTIVE: To evaluate the risk factors for breast cancer among women in Midwestern and Southeastern Nigeria. DESIGN: A case control study. SETTING: University of Benin Teaching hospital, Benin City and University of Port Harcourt Teaching Hospital, Port Harcourt in Nigeria. SUBJECTS: Fifty one women with diagnosis of breast cancer and their age- and sex matched controls were included in the study. INTERVENTIONS: Data was collected during a 30 minute period after obtaining written informed consent using interviewer-administered questionnaires. RESULTS: Parity > 4 (OR = 0.50, 95% Cl 0.17, 1.46) and duration of breast feeding > 60 months (OR = 0.58, 95% Cl 0.23, 1.48) were associated with reduced risk of breast cancer while birth order > 3 (OR = I.50, 95% Cl 0.25, 8.98), age at first full term pregnancy>20 years (OR = 2.50, 95% Cl 0.78, 7.97) and longer duration of reproductive period (OR = 1.25, 95% Cl 0.34, 4.66) were associated with increased risk of breast cancer. CONCLUSION: The study has shown that high parity and long duration of breastfeeding are associated with reduced risk while high birth order and late age at first full-term pregnancy are associated with increased risk of breast cancer.