The ovary produces three major sex hormones, oestrogens, progesterone and androgens.  Among the latter the most important biologically active hormone is testosterone. 

It is estimated that the ovaries are the source of approximately 50% of circulating testosterone. 

The major consequences of decreased ovarian function in women with premature ovarian failure (POF) are loss of oestradiol and progesterone; however, consideration should also be given to the possible loss of testosterone. 

Circulating testosterone levels fall by approximately 50% in normal women between the ages of 20 and 40.  There is little if any change at the time of menopause and hence a postmenopausal ovary can be regarded as primarily an androgen producing gland.  Its removal leads to a 50% fall in testosterone concentrations. 

When premature menopause is the result of surgical removal of the ovaries and probably when it is the result of chemotherapy or irradiation, androgen levels also fall by a similar amount. 

On the other hand whether testosterone falls significantly in women with other causes of POF is unclear with published data being conflicting and controversial.

Risks associated with POF

A group of women who may pose a particular concern are those with premature ovarian failure (POF) as a result of treatment for breast cancer.  Testosterone treatment should not be undertaken unless she is established on oestrogen replacement.  Although evidence is very limited, some experimental and clinical data suggest that testosterone may be breast protective.

Content updated August 30, 2006