The discovery is expected to prompt further studies around the world to better understand how ovaries and ovarian follicles develop in female fetuses.
This could be critical to treating or preventing a range of health conditions in later life, including infertility and ovarian cancer.
"For more than a decade, scientists have believed that ovarian follicle cells are derived from the epithelial cells on the surface of the ovary as it develops," said research leader Professor Ray Rodgers, from the University of Adelaide's Robinson Institute.
"Instead, contrary to conventional thinking, we've found a new cell type that is the precursor to both the cells on the surface of the ovary and the follicular cells. We call this the GREL (Gonadal Ridge Epithelial-Like) cell," he added.
Professor Rodgers said that this work could lead to new insights into a range of conditions, such as premature ovarian failure, early menopause, polycystic ovarian syndrome (PCOS) and ovarian cancer.
The study has been published in the journal PLOS ONE.