Women’s healthcare is severely under-researched, underfunded, and undervalued. The NIH policy advocating for the inclusion of women in research studies did not occur until 1986, and it was not legally required for women to be a part of NIH-supported clinical research until the NIH Revitalization Act of 1993. Women were often deemed to be “too complex” and unimportant in medical research, contributing to their underrepresentation and many medical advances being developed based on the male sex. As a result, female biology is still not completely understood and many women experience adverse effects from therapies originally tested on males.
Recently, a structure associated with the ovary that was previously thought to be vestigial in females, the rete ovarii, was “rediscovered.” While it was thought to serve no role in the past and was removed from biology textbooks since its initial discovery in 1870, preliminary findings suggest that it may be involved with hormonal signaling. Developmental biologist Jennifer McKey noticed a horseshoe-shaped structure at the bottom of mice ovaries and dug through old literature until she recognized it as the rete ovarii (Willcoxon, 2025).
She and her colleagues analyzed the RNA of the rete ovarii and determined that it contains many genes that were more highly expressed when estrogen levels were elevated. For example, one of the genes involved produces proteins that affect egg and follicle maturation, indicating it may play a role in fertility. In addition to its potential role in hormonal signaling, the rete ovarii contains blood vessels and nerves. It has been hypothesized that it may be able to interpret sensory input from the ovaries and release specific proteins in response (Willcoxon, 2025).
While the research is still in its early stages, this is one of many examples that illustrate how much remains unknown about female reproductive biology. If future studies establish that the rete ovarii serves a similar function in humans, findings may deepen our understanding of hormonal regulation, ovarian function, and fertility, possibly leading to new therapeutic approaches. However, additional research is needed to investigate the clinical significance and potential applications.
References:
Willcoxon, M. (2025, April 11). An overlooked organ may help the ovary function. Science News. https://www.sciencenews.org/article/rediscovered-organ-ovary-function.