Estrogen and inhibin.
Estrogen and progesterone.
Progesterone only.
Progesterone and inhibin.
Gonadotropin-releasing hormone (GnRH) is produced by the hypothalamus. It stimulates the pituitary gland to produce luteinizing hormone (LH) and, to a lesser extent, follicle-stimulating hormone (FSH). However, with depletion of follicular number, estrogen levels decrease with subsequent loss of negative feedback and resultant increases in GnRH secretion. Progesterone also decreases GnRH secretion at the level of the hypothalamus.