Case-control study of risk factors for breast cancer in Nigerian women: a pilot study.

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.