ABSTRACT
In positive feedback, an increase in the level of one factor leads to another action that serves to increase the level of the factor further still. Thus, the role of positive feedback mechanisms is not to stabilize or regulate a physiological parameter. In most cases, this could be detrimental, but it is used only rarely in physiological systems. A good example is the interplay between the hormones estrogen and luteinizing hormone (LH) in preparing for ovulation, where estrogen acts to release LH, which in turn leads to increased production of estrogen by the ovaries. The purpose of this positive feedback is to accelerate the development of ovarian follicles in preparation for ovulation.
