Introduction: The etiology of fibrocystic breast disease remains incompletely understood to date. It is likely primarily associated with ovarian endocrine dysfunction, absolute or relative increases in estrogen secretion, and persistent estrogen stimulation leading to proliferation of mammary epithelial cells. Research also suggests that this condition may be linked to inappropriate pregnancy and lactation history, psychological factors, dietary factors, and hypothyroidism.

Model Establishment: Female SD rats aged 8 weeks were acclimated for 1 week. The model group received daily intramuscular injections of estradiol benzoate at 0.5 mg/kg for 25 consecutive days. Starting on day 26, progesterone was administered intramuscularly at 4 mg/kg daily for 5 consecutive days.
Molding cycle: 30 days
Maturation rate and mortality rate: Maturation rate is approximately 90%, mortality rate is approximately 10%.