If someone asked you to name the hormones that are important to women, what would come to mind? Most people would say estrogen. Some might think of progesterone. Very few would mention testosterone — and that’s understandable, because for decades testosterone has been described almost exclusively as a male hormone.

But that simply isn’t accurate. Testosterone is a human hormone. Women naturally produce it throughout their lives, in their ovaries and adrenal glands, where it plays an important role in normal physiology. And here is something that surprises almost everyone: during much of a woman’s reproductive years, her body produces more testosterone each day than estrogen.

That isn’t because testosterone is more important than estrogen. The two hormones have different jobs. Estrogen is essential for reproductive health, bone strength, and many aspects of cardiovascular and brain function. Testosterone contributes to energy, motivation, lean muscle maintenance, sexual function, cognitive performance, and overall wellbeing. Both matter. Both deserve attention.

Unfortunately, testosterone has remained largely absent from conversations about women’s health. As a result, many women spend years trying to understand why they feel different — without ever realizing that testosterone could be one piece of the puzzle.

We aim to change that conversation.