In general, sex drive decreases gradually with age in both men and women, but women are two to three times more likely to be affected by a decline in sex drive as they age. Reduced sex drive becomes much more common in women starting in their late 40s and 50s. The effect of age also differs by the individual: some women experience a big decrease in sexual desire beginning in their midlife years, others notice no change, and a few report increased interest in sex at midlife. During the menopause transition, the physical effects of falling estrogen levels—including hot flashes, night sweats, and vaginal dryness—can undermine sexual motivation and drive. Although, the precise role of testosterone in desire is complex, however, low sexual desire in women has not been shown to be related to testosterone levels in scientific studies.