Factors affecting age at natural menopause in Korean women: smoking, body mass index, and prior childbirth


Park Chan Young, Lim Joong-Yeon, Park Hyun-Young, Kim Won-Ho
Division of Cardiovascular Diseases, Center for Biomedical Science, KNIH, KCDC

Background: Age at natural menopause (ANM) is an important indicator of health issues in older women and is associated with menopausal symptoms, various chronic diseases and quality of life. However, research on the trends and influencing factors of ANM is insufficient. Therefore, in this study, we sought to identify such trends and the lifestyle factors influencing ANM.
Methods/Results: Totally 12,761 natural menopausal women were selected from the Korea National Health and Nutrition Examination Survey (2001-2014). The mean±standard error of their ANM was 49.3±0.1 years. ANM was found to be associated with birth year, showing an upward trend of 0.73 years per five birth years. We evaluated the mean differences in ANM according to lifestyle factors, after adjusting for all confounders. The ANM of smokers was 0.55 years earlier, on average, than that of non-smokers (P = 0.024), and each 1 kg/m2 increase in body mass index (BMI) delayed ANM by 0.07 years (P < 0.001). It was found that ANM in women who had experienced childbirth was 1.59 years more than that of women with no childbirth experience (P < 0.001).
Conclusion: As the life expectancy of women increases, there is greater emphasis on the importance of healthcare for older women. In this study, we found that the mean ANM is on the upward trend and smoking, body mass index, and prior childbirth are independently influencing ANM.

Keywords: Age at natural menopause, Natural menopause, Menopausal trend, Lifestyle factors, Women health