The trial of Procter & Gamble's Intrinsa testosterone patches for women was sponsored by Procter & Gamble and the treatment was indicated for hypoactive sexual desire disorder (HSDD).

“HSDD is characterized as a lack or absence of sexual fantasies and desire for sexual activity for some period of time”, Wikipedia states.  An estimated 26.7% among premenopausal women and 52.4% among naturally menopausal women had the condition, according to another study published in the July 2008 issue of Archives of Internal Medicine.

The results of the current trial showed that at 24 week, the 4-week frequency of satisfying sexual episodes increased in women who receive 300 ug per day to 2.1 compared to 0.7 in those who did not receive the treatment.

In the double-blind, placebo-controlled 52-week trial, researchers tested two doses, 150 ug and 300 ug of testosterone per day or placebo in 814 women with hypoactive sexual desire disorder.

The researchers also found that 150 ug per day of testosterone did not have any effect in terms of sexual episodes.   But both doses were associated with significant increases in desire and decreases in distress.

The adverse effects observed during the one-year trial included an increased risk of breast cancer and hari growth.  Breast cancer was diagnosed in four of the 534 women treated with the male hormone, but none in the 277 placebo recipients.

The participants will be followed up for another year to evaluate the safety of this treatment.

Susan Davis of Monash University in Melbourne, Australia and colleagues concluded in their report that "In postmenopausal women not receiving estrogen therapy, treatment with a patch delivering 300 µg of testosterone per day resulted in a modest but meaningful improvement in sexual function. The long-term effects of testosterone, including effects on the breast, remain uncertain."

In response to the trial, a health observer who did not want to be named suggested that any medical treatment for low libido in postmenopausal women is not necessarily justified.   Sexual desire and performance varies from person to person and decline naturally. Those who engage in less active sexual activities do not necessarily have any real disorder.   Any treatment could be just against nature and potentially do more harm than good.

Procter & Gamble has been trying to get Food and Drug Administration’s approval for its Intrinsa testosterone patches for women. In December, 2004 a 14-member FDA advisory committee unanimously rejected the treatment citing concerns about the lack of long-term safety data and off-label use.