Estrogen receptors first appear in the epithelium of the fetal breast.
Duration: 14 weeks
Howard BA, Gusterson BA. 2000. Human breast development. Journal of Mammary Gland Biology and Neoplasia 5(2):119-137.
Preantral follicles, which contain a large oocyte with a zona pellucida, multiple layers of granulosa cells, and a thecal cell layer (originating in the stroma) begin to develop at the border of the cortex and medulla.
Rabinovici J, Jaffe RB. 1990. Development and regulation of growth and differentiated function in human and subhumand primate fetal gonads. Endocrine Reviews 11(4):532-557.
Thecal cells (capable of steroidogenesis) are present.
Duration: 14 weeks
Rabinovici J, Jaffe RB. 1990. Development and regulation of growth and differentiated function in human and subhumand primate fetal gonads. Endocrine Reviews 11(4):532-557.