Correlative Factors puberty o An estrogenic milieu may be necessary 青春期 o Progesterone function menopause 绝经期 estrogen progesterone 雌激素 孕激素 o Growth factor and their receptor epithelial growth factor (EGF Insulin-like growth factor (IGF) platelet-derived growth factor 2003-11-3 42003-11-3 4 Correlative Factors An estrogenic milieu may be necessary Progesterone function Growth factor and their receptor： epithelial growth factor（EGF） Insulin-like growth factor（IGF） platelet-derived growth factor puberty 青春期 menopause 绝经期 estrogen 雌激素 progesterone 孕激素