Testosterone is a female hormone too
Testosterone is often thought of as a male hormone however it is an important hormone in women too. Unlike oestrogen which declines very sharply with the menopause, testosterone, which is produced by the ovaries and the adrenal glands, starts to decline very slowly from the 20s or 30s. The level of testosterone in women in their 60s is around half that seen in women around 30 years of age. While the value of oestrogen replacement is well established the value of testosterone is often unrecognised.
The value of testosterone
Oestrogen replacement will alleviate the symptoms of the menopause including hot flushes mood swings headaches insomnia mood swings and loss of libido. This results in improved quality of life. HRT will also prevent osteoporosis and reduce the incidence of heart disease leading to increase in life expectancy in women taking HRT. However, some women taking HRT continue to experience symptoms despite taking adequate oestrogen. These symptoms typically include low mood, anxiety, tiredness and loss of libido. The benefit of giving testosterone as well as oestrogen was first described by Robert Greenblatt more than 60 years ago, who reported that women taking oestrogen but who continue to experience these symptoms will benefit from the addition of testosterone. Since that original study a number of studies have reported on the value of testosterone.
It is important to note that most studies on the use of testosterone in women have focussed on loss of libido. It is not surprising therefore that the strongest evidence in the scientific literature relates to sexual function and loss of libido in particular. More recently, Professor Studd has described the value of testosterone in the treatment of other postmenopausal symptoms including low moods, headaches and tiredness. There is some evidence that the effects of testosterone on moods is due to its effect on serotonin.
Antidepressants are unhelpful
Depression and anxiety are common in women around the time of the menopause, especially in those women who have suffered from premenstrual syndrome or post-natal depression. Antidepressants are commonly prescribed for these women, but they are often unhelpful and often aggravate symptoms such as loss libido, tiredness, poor sleep and weight gain. Women with PMS and menopausal depression are best treated with oestrogen and testosterone replacement. Not only is this more effective it will also help with other menopausal symptoms, and reduce the risk of osteoporosis and heart disease.
The addition of testosterone in women receiving oestrogen replacement can increase muscle mass and some studies have shown that oestrogen and testosterone combination may be better than oestrogen alone in preventing osteoporosis.
Heart disease risk higher with lower testosterone
There is a perception that testosterone is a male hormone and can have serious side-effects, particularly in women. There is a misconception that testosterone may increase the incidence of heart disease, because men who have higher testosterone levels than women are more prone to heart disease, but this is not correct. Laboratory studies have not shown testosterone to be associated with adverse changes in cholesterol. The emerging evidence suggests that testosterone may in fact be protective against heart disease; men with low testosterone have a higher risk of heart disease than men with normal circulating testosterone. Furthermore, a study from Sweden has shown that the incidence of heart disease was higher in women with low testosterone even when controlled for either risk factors.
Women are often anxious about taking testosterone for fear that this will increase growth of facial hair. Facial hair growth increases in women after the menopause and oestrogen replacement can reduce this. The use of testosterone in women who are also taking oestrogen increases the risk of hair growth very mildly but it is rarely severe enough to stop. In any case facial hair growth is reversible if the dose of testosterone is reduced or stopped.
In the UK there are currently no licensed testosterone products for women despite the fact that the NICE guidelines recognise the value of testosterone in the treatment of loss of libido in postmenopausal women receiving oestrogen replacement. In the past a testosterone patch was available but the manufacturers removed this from the market several years ago for commercial not medical reasons. We tend to prescribe testosterone gels that are licensed for men but in a much reduced dose. Men requiring testosterone are usually prescribed one sachet of Testogel per day, women are asked to take one eighth of sachet every day, so that one sachet is used over 8 days. Testosterone can also be given as implants, a pellet of testosterone, usually with oestrogen is inserted under the skin as an outpatient procedure every six months. Oral testosterone should be avoided as it is associated with adverse effects on liver function. Hormone levels are usually measured prior to commencing treatment and the levels are checked while on treatment to ensure that each woman receives the correct dose for them.
Why combination of oestrogen and testosterone is better
Oestrogen replacement is safe and effective in the treatment of menopausal symptoms and preventing osteoporosis but the combination of oestrogen and testosterone is better, particularly in those women who have had a premature menopause or have had their ovaries removed. It should also be considered in women who continue to experience symptoms of loss libido, depression, mood swings headaches and tiredness despite taking oestrogen.
The time of a woman’s life when her ovaries stop releasing an egg (ovum) on a monthly cycle, and her periods ceaseFull medical glossary