Puberty is a dynamic process that occurs as young women emerge into their reproductive lives. The prepubertal process begins in the hypothalamus. There, gonadotrophin-releasing hormone neurons secrete gonadotrophin-releasing hormone (GnRH). Gonadotrophin-releasing hormone, in turn, enters the portal system in pulses, stimulating the pituitary to produce luteinizing hormone (LH) and follicle stimulating hormone (FSH), both of which act on the maturing ovary to initiate the production of estrogens and androgens and then progesterone once ovulation occurs. Once produced, rising levels of estrogen communicate back to the hypothalamus to slow the process. But how does estrogen control this feedback process since there are no estrogen receptors on the GnRH neurons? And what does this have to do with menopausal hot flashes?