Objectives: To assess the prevalence of hormone replacement therapy (HRT) among Norwegian women and examine factors related to use.
Materials and methods: A random sample of 18,199 Norwegian women aged 45-64 years responded to a postal questionnaire in 1996-1997. The questionnaire included questions about menstruation status and fertility, oral contraceptives (OC) and HRT use, lifestyle, health and socio-economic status. The response rate was 60%.
Results: Overall prevalence of ever using systemic or local HRT was 43.9%. Current use was reported by 31.9% of the women. The highest prevalence was in the age group of 55-59 years where 57.4% reported ever use, and 43.1% current use. Mean duration of use among current users was 4.6 years. More than 60% of the women were classified as postmenopausal, two-thirds of them naturally postmenopausal. The prevalence of ever using HRT was 51.8%. Prevalence of use was higher among earlier OC users, smokers, lean women and in households with high income. Among older women, users had a higher educational level than non-users, while this difference disappeared among the youngest of the women. Fixed combinations of estradiol and noretisteroneacetate either cyclic or continuous, are used by six out of ten users.
Conclusions: Our results confirm the increasing trend in sales of estrogens in Norway and suggest that user patterns are changing. More than four out of ten women aged 45-64 years reported ever use of HRT, and one out of three reported current use. Socio-economic differences between users and non-users seem to disappear among women under 55 years of age, but persist in the older age groups. Short time use still dominates.