Forgotten and Overlooked Structure Attached to the Ovary May Be Far More Active Than Once Thought

The rete ovarii (RO) is a small structure attached directly to the ovary that has largely faded from view since it was first described more than a century ago. Its name comes from the Latin word for “network,” referring to the interconnected tubes and channels that make up the structure, according to the National Cancer Institute.

There is a similar structure in males called the rete testis, which sits inside the testicles and helps transport sperm. But unlike its male counterpart, the RO was never assigned a clear role in the female reproductive system. Over time, it was often dismissed as a leftover structure with little or no function and eventually disappeared from many anatomy textbooks.

Now, recent research from a study published in eLife in March 2025 is bringing this overlooked part of the ovary back into focus. A closer look using modern imaging and molecular techniques suggests that the RO may be far more active and complex than scientists once thought.

Sign up for Blog Updates