Hot flushes, menstrual status, and hormone levels in a population-based sample of midlife women

To determine the frequency of hot flushes in a population sample of 453 pre-, peri-, and postmenopausal women (aged 48-59 years), and to investigate the relationship of hot-flush reporting with menstrual status, serum levels of estradiol (E2), inhibin, and FSH, history of premenstrual complaints, and physical and life-style factors.

We used a population-based sample. Interviews were conducted in the women's homes.

Frequency of hot-flush reporting was associated with menstrual status (P < .001). Twenty-nine percent of women who had more than 3 and less than 12 months of amenorrhea, and 37% of postmenopausal women experienced hot flushes several times a day. In total, 13% of premenopausal women, 37% of perimenopausal women, 62% of postmenopausal women, and 15% of women on hormone therapy reported having had at least one hot flush in the previous 2 weeks. Follicle-stimulating hormone levels were higher in women who experienced hot flushes at least once a day or more (P < .001); E2 levels were higher in women experiencing one or no hot flushes per week (P < .001). The women in the perimenopausal group who experienced hot flushes had higher FSH levels (P = .008) and were more likely to have reported premenstrual complaints at the first interview 3 years earlier (P = .03). In the postmenopausal group, there was no significant difference with any of the variables studied between the women who were experiencing hot flushes and those who were not.

Reporting of hot flushes is greatest 3 months or more after the final menstrual period. The frequency of hot flushes is associated with increasing FSH, decreasing E2, and a history of premenstrual complaints.