The aim of this study was to examine if the previously found trend of increasing menopausal age is continuing, taking into consideration hormonal use and surgical menopause in both 38- and 50-year-old women of today.
Cohort comparisons of five generations of population-based samples of 38- and 50-year-old women from the Prospective Population Study of Women in Gothenburg with start in 1968/1969, and with follow-ups in 1980/1981, 1992/1993, 2004/2005, and 2016/2017. Across the time periods newly recruited women as well as earlier participants were included. Use of hormonal contraceptives, estrogen plus progestogen therapy (EPT), and time for menopause was registered. Changes between different generations of 38- and 50-year-old women from 1968/1969 until today were studied. The overall sample size across the time periods was 1,873 individuals.
The prevalence of oral contraceptives in 38-year-old women was about 10% in 1968/1969, increasing from 16% in 2004/2005 to almost 22% in 2016/2017. From 2004/2005 the use of hormonal intrauterine contraceptive method (the Levonorgestrel-releasing intrauterine system [LNG-IUS]) increased from about 11% to 14% in 2016/2017. The same pattern was found in 50-year-old women using LNG-IUS, increasing from 6% to 15.5% between 2004/2005 and 2016/2017. The total hormonal use, including LNG-IUS, oral contraceptives, and EPT, was 28% in 50-year-old women in 2016/2017. The total proportion of hormone use in 50-year-old women increased over the years and together with surgical menopause it reached over 37% in the 2016/2017 survey.
This study has shown an increase in the hormonal use, in both 38- and 50-year-old women, making it difficult to determine when the actual menopause occurs. Thus, the previously found increasing secular trend in menopausal age will be more complicated to assess in female generations of today and tomorrow.