Libido is, at best, complicated. Testosterone is the hormone that is linked to libido for women as well as men. After about age 25, our testosterone levels are slowly dropping. It’s estimated that a 50-year-old has about half the testosterone she once had.
I see this phenomenon with increased libido in perimenopause from time to time. Testosterone interacts with other circulating hormones, and it seems to be the relative balance and interaction of these hormones, not the absolute levels of each, that for some women works very favorably during perimenopause. Relatively speaking, testosterone may have some “dominance,” even though the levels are lower than they used to be. Enjoy!
There are some other possible factors: Obese women tend to have slightly higher testosterone levels, and some women have had weight gain in perimenopause. Or, because we’re complicated sexual creatures, it could be the empty nest or something else entirely (for some, the absence of "that bothersome uterus").
In general, women do experience a loss of libido with menopause, but the loss is not uniform across the board. We can hope you are that woman who doesn’t lose interest. In the meantime, seize the moment!
If you’re wondering when you might move from perimenopause to menopause, I’m afraid we can’t accurately predict that timing. We can only say that women, on average, become menopausal about age 50. Ninety percent of women have four to eight years of changed—and changing—menstrual patterns before becoming menopausal. Blood work is accurate in understanding estrogen, progesterone, and FSH levels for the day of the test, but it doesn’t accurately predict anything. Testosterone levels have fewer day-to-day fluctuations, so accurate measures can be made.
Perimenopause is a time to tune into your body, because as you move into menopause, your symptoms will be the best indicator of what’s actually happening.