| The idea is that progesterone is the raw building material for a number of hormones, one of which is testosterone. In peri-menopause, our testosterone production drops dramatically. Testosterone is one of the key hormones influencing libido (but not the only thing involved in sexual response). Some of us can compensate for its decline; others cannot. The situation is worsened by taking estrogen, in a way, in that estrogen increases levels of a protein that binds testosterone. When you have fully-functional ovaries, these things balance out: you make enough testosterone to still have enough left after the protein gloms its share. When your ovarian production goes down, as in menopause, and you take HRT that contains estrogen, you are in effect hitting the testosterone with a double whammy: lower output and the protein to skim off what you do have. By adding progesterone, some women find they are able to manufacture enough testosterone again to regain their libido. Others, in whom the libido loss is due to some other problem, may not find progesterone helpful in that regard (although it may or may not be in other ways). Generally speaking, there's no way to tell whether it will help or not without trying it. But oral progesterone should work for this as well as the cream does. There are women for whom oral progesterone is ineffective--either because they do not absorb it or they too readily get rid of it--and for them, a trial of the cream form may be useful to see if it's route-related. The main difference between oral and cream seems to be that the oral route produces more sedating metabolites; otherwise, they should work the same way. |
