Characteristics of HRT users in Japan: Evidence from the Japan Nurses' Health Study

•We determined the characteristics of new users of hormone replacement therapy (HRT).•Women who worked as public health nurses and midwives were more likely than registered nurses to use HRT.•Women who had used oral contraceptives were likely to use HRT.•Advanced age at menopause was significantly associated with a low rate of use of HRT. Little is known about what type of women use hormone replacement therapy (HRT) in Japan. Based on the Japan Nurses' Health Study (JNHS), a large population cohort study, we determined the characteristics of HRT users by comparing the characteristics of new HRT users and the characteristics of women who did not use HRT during a 10-year follow-up period. Of the 15,019 JNHS participants, 4886 women reported an experience of menopausal transition during the 10-year follow-up period. Characteristics of new HRT users. The proportion of HRT users during the 10-year period was 8.5 %. Advanced age at menopause was significantly associated with a low rate of use of HRT. Past use of oral contraceptives, dysmenorrhea with disturbance in daily life and vasomotor symptoms were significantly associated with a high rate of use of HRT. The occupations of public health nurse and midwife and a history of bilateral oophorectomy were also significantly associated with a high rate of use of HRT. We determined the characteristics of new HRT users among middle-aged women during a 10-year follow-up period. Women who had sufficient knowledge about endocrinological hormones and women who had less reluctance to visit doctors for gynecological problems were likely to use HRT.