A tiny female reproductive structure dismissed as useless and dropped from anatomy textbooks for decades may actually play a major role in ovarian health and fertility, new research suggests.
The rete ovarii, first described in humans in 1870, appeared in early editions of Grey’s Anatomy before quietly disappearing from medical texts. For a long time, researchers classified it as a “functionless vestige” – a leftover with no purpose.
But a Duke University Medical Centre team has found the horseshoe-shaped structure is far more active than previously believed. Their research, published in eLife, identified three distinct regions of the rete ovarii and found that fluid flows in one direction: from the structure into the ovary.
Researchers also found that the rete ovarii secretes proteins, including IGFBP2, which aids in regulating follicle development. The structure also responds to estrogen, contains hormone receptors, and sits near blood vessels, nerves, and immune cells – leading scientists to describe it as an “antenna” for the ovary.
One of the researchers, Blanche Capel, said: “We think it is regulating the timing or rate of ovulation. We could perhaps use it somehow to extend the female reproductive lifespan.”
The findings have sparked outrage online, with critics pointing to a long history of neglecting women in health research. The National Institutes of Health didn’t require women in federally funded clinical trials until 1993.
