In vitro culture of ovarian follicles.

This review offers a practically oriented introduction to follicle culture in vitro, focusing on mouse follicles, but with reference to other species. The main principles of follicle growth are addressed, including the constraints of tissue culture, methods of follicle isolation, and techniques for individual and collective culture of intact follicles. Culture systems that support a spherical or a non-spherical follicular structure in vitro are discussed in terms of follicular and oocyte development, and methods for assessing follicular function in vitro are presented. Oocyte development in most in vitro culture systems is currently suboptimal and the parallel development of oocytes and follicles is discussed, with a view to maintaining the competence of the oocyte. Finally, some potential future applications of follicle growth in vitro are suggested.