A composition comprising microcapsules, the microcapsules containing both live mammalian ovarian granulosa cells and live mammalian ovarian theca cells, is described. In some embodiments, the granulosa cells and the theca cells are contained in separate microcapsules in the composition; in some embodiments, the granulosa cells and the theca cells are contained together in the same microcapsules in the composition The composition is can be used for estrogen, and optionally also progesterone, delivery, and hence is preferably free or essentially free of oocytes. Methods of using the same and pharmaceutical formulations containing the same are also described.