There are no official numbers for the optimal levels of testosterone. However, certain medical laboratories use the following reference values for typical total serum testosterone, measured in ...

Testosterone is almost always talked about as a male hormone, but it exists in women also, and when its levels are too high, it can significantly affect fertility. From disrupted ovulation to hormonal ...

This article was made possible by the support of Yakult and produced independently by Scientific American’s board of editors. More than 20 years after menopausal hormone therapy fell out of favor, it ...