Women normally have circulating in their blood 3 major sex hormones: oestrogen, testosterone and progesterone. Each of these is produced by the ovaries. Oestrogen is also made throughout the body but particularly in body fat. Testosterone can also be made in other parts of the body from hormones (DHEA and DHEAS) that are produced by the adrenal glands.

At the time of natural menopause or surgical removal of the ovaries oestrogen and progesterone levels fall precipitously.

Testosterone and DHEAS levels however fall more gradually with increasing age such that a woman in her forties has on average only half of the testosterone and DHEAS circulating in her bloodstream as does a woman in her twenties. After a woman has her ovaries removed by surgery testosterone levels can fall by up to fifty percent. However testosterone does not change across menopause, although this varies somewhat between women.

Testosterone and other related hormones (DHEA and DHEAS) in the body (also known as androgens) have known physiological roles in women. Firstly, oestrogen is actually made from testosterone and DHEA, and without the ability of our bodies to make testosterone we cannot make oestrogen. Testosterone and DHEA appear to have direct independent effects in different parts of the body, and some women may experience a variety of physical symptoms when their blood levels fall. Such symptoms may include:

• impaired sexual interest (loss of libido or sexual desire), and lessened sexual responsiveness

• lessened wellbeing, loss of energy.

Testosterone therapy may be beneficial for some women who have had their ovaries surgically removed or in some cases who have significant symptoms in the form of loss of libido, fatigue and diminished wellbeing.