Testosterone improves sexual function in post-menopausal women

One of the more common, but less discussed symptoms of the post-menopausal state is the decrease in libido. Due to its sensitive nature, many women do not even share this concern with their providers. However, those who suffer from it should know that they are not alone.

Many times, in addition to the basic desire and responsiveness being diminished, due to the atrophy that may take place within the female genitalia, pain and tearing may be a common occurrence with physical intimacy. If chronic, this may decrease or eliminate the desire for intimacy, as it is associated with pain.

In this case, topical estrogen may be used, but testosterone cream has also been known to strengthen the epithelium of the genitalia.

There have been many studies which have looked at the efficacy of testosterone in the post-menopausal woman and its effect on sex-drive. These have all been credited with being well-conducted studies, most of which have shown a modest improvement in desire, responsiveness and satisfaction. The limitation on these studies has been their short duration of 3-6 months, which curtails the knowledge that we have of the risks of its long-term use.

Testosterone is made in small amounts in the female ovarian cycle. It is necessary for the control of ovulation and is also responsible for a woman's sex drive. Naturally, as the female production of testosterone is much lower than that of the male, there is a discrepancy in the libido experienced by each gender. For many women, whom have reached menopause and experienced the failure of the ovaries, this gap is widened, as testosterone production lessens.

Needless to say, this can create any variety of problems in a marriage or union, and, certainly, deserves to be addressed.

For some women, merely replacing Estrogen or Estrogen and Progesterone may be sufficient; however, there remains a significant percentage for whom this will not have any noticeable impact. Consequently, although, it has been an off-label indication, testosterone has been used for many years, to address this.

This study published in the New England Journal of Medicine has recently published results from its phase III clinical trials of Female Sexual Dysfunction of Women on Testosterone without Estrogen. It was a study conducted on only 814 women, however, some of its statistical power lay in its sampling of women from 65 different centers from the US, Canada, Australia, the UK and Sweden. Further, it is a landmark study among its peers in that it is the first to examine data through 52 weeks, and to even host a second year of treatment in order to monitor for adverse effects.

The subjects were randomized into three groups: one receiving 150 micrograms of testosterone; one receiving 300 micrograms and one placebo group. They were assessed through a Profile of Female Sexual Function and a Personal Distress Scale which were administered at 24 and 52 weeks. The were further seen at baseline and at 6, 12, 24, 36 and 52 weeks.

Baseline scores were uniform among all three groups regarding frequency of satisfying events, desire and distress. By week 24, the increase in 4-week frequency of satisfying events was significantly greater in the 300 microgram group with an increase of 2.1 episodes vs. an initial 0.7 for placebo. The 150 microgram group experienced a proportional increase of 1.2 fulfilling episodes in 4 weeks. Both medicated groups had significantly increased scores for desire and diminished scores for distress by week 24.

The incidence of adverse events was similar in both medicated groups, with androgenic changes being the greatest problem. These included male-patterned hair growth, acne, alopecia and voice-deepening, of which hair growth was the most common. The biggest problem with these complications is that, once stimulated, the testosterone receptors in the respective tissue cannot be inhibited. Therefore, the physical changes cannot be reversed. Hypersensitivity to the patch site was the most frequent side effect, occurring in roughly half of all three subject groups. The most concerning observation, however, were the four cases of breast cancer. While this may have been due to chance, there is not enough known about the link between breast cancer and testosterone to eliminate this as a concern in long-term use. Further, in vivo, it is a well known fact that testosterone can adversely affect the lipid profile and increase the likelihood for cardiovascular disease. However, it still remains uncertain whether exogenous testosterone will have the same impact.

Patterns of efficacy were apparent for women with naturally occurring menopause, but did not seem to exist for those whom had undergone a surgical menopause (removal of both ovaries). It is possible, however, that the numbers of women in this group were too limited to draw any valid conclusions from this.

This may also hold promise for pre-menopausal women whom also suffer from a low sex drive, possibly due to decreased production of testosterone for unclear reasons. A free testosterone level should be drawn and assessed. Certainly if her production is low, it might be worth trying the therapy. It is unclear whether other causes of decreased sex drive like stress, chronic fatigue or chronic illness will respond to this therapy.

Transdermal testosterone is available in Europe for women whom have decreased libido and no response to conventional HRT. However, due to the incomplete information available about long-term use, the FDA has yet to approve it in the US for this indication. For this reason, it can only be obtained as a compounded drug through pharmacies that specialize in the technique. While this option exists and is not illegal, due to the lack of large double-blind prospective studies, it is important that full disclosure of all risks and benefits be given.