Abstract
BACKGROUND: Substantial evidence supports a causal relationship between the risk of human breast cancer and levels of endogenous estrogens. AIM: To evaluate the urinary estrogen of women on contraceptives and also compare the levels in two different classes of contraceptives; hence, the possible predisposition of such women to the risk of breast cancer. SETTING AND DESIGN: Urinary estrogen level was evaluated in 84 women attending family planning clinic in University of Nigeria Teaching Hospital Enugu, Nigeria, who have been on contraceptive device for 10 years or less (≤10 years). They were aged between 21 and 50 years and were divide into three groups (21-30 years, 31-40 years, and >40 years). The control group consisted of 30 age-matched apparently-healthy women who were not on any contraceptive device. MATERIALS AND METHODS: Estrogen was analyzed using Ecologenia(;) Estrogen (E1/E2/E3) microplate enzyme-linked immunosorbent assay (ELISA) kit, Batch No. T2GR4, from Japan Envirochemicals Ltd, Japan. STATISTICAL ANALYSIS USED: Significant differences between means were determined by two-tailed Student's t-test using graph pad prism computer software program. RESULT: There was a statistically significant increase (P=0.0462), in the mean urinary estrogen level of women on contraceptives when compared with the control. The highest amount of estrogen was excreted by the women in the 21-30 years age group. When the contraceptive devices were divided into two classes of intra-uterine device and oral/injectables, there was no statistical difference (P=0.8112) in the mean urinary estrogen output of the women. CONCLUSION: The synthetic estrogen content of contraceptive device most probably contributed to the level excreted in the urine. The increased estrogen output observed in women on contraceptive device was not dependent on the class of contraceptive device used.