Abstract : Prepubertal vaginal bleeding is considered as isolated menarche, when thorough medical examination does not show other signs of sexual development or any detectable uterine or vaginal abnormalities (infection, foreign bodies, tumors, trauma…). If other puberty signs (thelarche, pubarche, peak of growth…) develop, the vaginal bleeding will not be isolated any more and we will consequently speak of true early puberty. It is thus the follow-up of the patient which will allow to make the differential diagnosis between precocious and benign isolated menarche and true early puberty determining the statural future and requiring a specific treatment. The etiology of prepubertal menarche remains unclear, and more research is needed to establish causation. Several complementary examinations must be carried out in order to exclude tumoral, infectious, traumatic or hormonal pathologies and those must be repeated during the follow-up of the patient.