The final effect is a decrease in fibroadenoma dimensions, considering that the stromal compartment is responsible for fibroadenoma size.42 This theory was corroborated by our findings, in which we observed lower expression of Ki-67 and c-myc (9.2 and 10.5, respectively) in group 1 (oral contraceptive plus placebo), as shown in Table 6. This evidence concerns the gene MKI67 and Fibroadenoma.