The influence of premenopausal hormones on severity of climacteric symptoms and use of HRT

Objectives There is wide variation in the severity of climacteric symptoms and we hypothesized that this could be a reflection of premenopausal hormone levels. Methods As part of a long-term cohort study of endocrine risk factors for breast cancer, blood had been collected between 1986 and 1990 from 1882 premenopausal women aged >= 35 years. Questionnaires on menopausal symptom severity were sent to 1843 surviving women in 2001, of whom 1434 replied. Estradiol, progesterone and testosterone levels were measured by radioimmunoassay in 680 women who reported a natural menopause and completed the symptom severity section in full. Results Symptom severity fell with rising premenopausal estradiol levels and women with higher premenopausal testosterone levels had more severe vasomotor symptoms. Over 70% of women with above-median severity of symptoms had used hormone replacement therapy (HRT). Those with higher testosterone levels were less likely to take HRT. Conclusions Premenopausal hormone levels may predict risk of severe menopausal symptoms, which in turn influences use of HRT. Paradoxically, a high testosterone level was associated with more vasomotor symptoms but reduced use of HRT. Those at greatest risk of climacteric symptoms may be at lower risk of breast cancer because of premenopausal reduced estrogen exposure.