[Role of FSH and LH in follicle development]

Much of the research into the physiology of the ovary has concentrated on the terminal stages of follicle development, and as a result, our knowledge of the endocrine, paracrine, and autocrine mechanisms regulating antral follicle development is extensive. In contrast, our knowledge of the factors controlling the initiation and development of earlier follicles is limited, particularly in monovular species such as large domestic ruminants and humans in whom it takes several months for follicles to progress from initiation to the antral stage. This study summarizes recent data concerning the factors controlling the initiation and development of follicles from the primordial through the preovulatory stage of development.