At approximately day 1

Anti-Mullerian Hormone detected in granulosa cells.

Reference [PubMed Link]

Rajpert-De Meyts E, Jorgensen N, Graem N, Muller J, Cate RL, Skakkebaek NE. 1999. Expression of anti-Mullerian hormone during normal and pathological gonadal development: association with differentiation of Sertoli and granulosa cells. Journal of Clinical Endocrinology & Metabolism 84(10):3836-3844.