Which steroid hormone serves as a sex hormone for female mammals?

Oestradiol is a key steroid hormone that plays a critical role as a sex hormone in female mammals. It is a form of estrogen, which is essential in the regulation of various physiological processes, including the menstrual cycle, reproductive system, and the development of secondary sexual characteristics. Oestradiol influences the growth and maintenance of female reproductive tissues and also impacts bone health and fat distribution in the body.

The action of oestradiol is mediated through estrogen receptors, which are present in many tissues, allowing it to exert significant effects beyond reproduction. Its synthesis primarily occurs in the ovaries, but it can also be produced by the placenta during pregnancy and some other tissues in the body.

Understanding the distinct role of oestradiol as a female sex hormone helps clarify its importance in both reproductive and non-reproductive health, making it essential in studies related to female development, fertility, and overall well-being.