Various correlations of testosterone metabolites during puberty were modulated in female rats. It has been fixed that estrogenes stimulate female pubescence only under conditions of non-aromatized androgenes availability in organism. Role of estrogenes in first-stage puberty (vagina opening) consists in activation of fermentative (5a- reductive) system which realises testosterone biotransformation into 5?-reduced androgenes. Being dependent on the dose estrogenes shorten the period between initial and final (establishing positive feed-back way in ovaries-hypophysis system) puberty stages, hasten the first ovulation