Control and regulation of folliculogenesis--a symposium in perspective.

The Intervet Symposium 'Control and Regulation of Folliculogenesis' took place at the Annual Conference of the Society for the Study of Fertility in University College, Dublin in July, 1995. Five papers were presented, of which abstracts have been published. Discussion centred on monotocous species and principally addressed the question 'How is the ovulatory follicle selected and nurtured?' Many follicles start to develop simultaneously, but most become atretic. During the luteal phase of the cycle, several waves of follicles are initiated, and although one in each wave gains dominance, all ultimately atrophy. The dominant follicle in the wave produced towards the end of the luteal phase ovulates. The biochemical characteristics of dominant and subordinate follicles were contrasted, and the endocrine environment in which they waxed and waned was analysed. Interaction of autocrine and paracrine effectors, principally with FSH, LH and their receptors, ultimately determines follicular destiny.