A hormone produced by the hypothalamus of the brain to regulate production and release of the gonadotropins follicle stimulating hormone and luteinising hormone. Can be administered to induce ovulation when it is deficient (particularly in amenorrhea due to weight loss or excessive exercise), but it has to be given in small amounts directly into a vein, every 60 to 90 minutes for the two weeks of a normal follicular phase (with an electronic syringe-driver), mimicking its natural pattern of secretion.

Synthetic hormones related to the natural hormone GnRH, or gonadotropin releasing hormone.

Part of the brain lying immediately above (and connected to) the pituitary gland; responsible for producing gonadotropin releasing hormone and dopamine, among other hormones and substances (including the endorphins, serotonin, etc.). In women (when conditioned to cyclical function by a lack of exposure to male sex hormones before birth) it resonates with the ovarian cycle and cooperates with the pituitary gland to cause corresponding cyclical production of follicle stimulating hormone and, particularly, a timely LH surge. Responds to progesterone by raising the body's temperature

Congenital absence of gonadotropin releasing hormone in the hypothalamus (causing, in women, primary amenorrhea and anovulation and, in men, failure of puberty) in combination with a congenitally absent sense of smell.

Gland located at the base of the brain and responsible (among other jobs) for driving the ovaries in women and the testes in men by way of the pituitary hormones follicle stimulating hormone (FSH) and luteinising hormone (LH), which are under the influence of gonadotropin releasing hormone (GnRH) from the hypothalamus. Composed of two parts, the adenohypophysis, or truly glandular part, in front, and the neurohypophysis, which is a down-growth of the brain, behind.