Helping midlife women predict the onset of the final menses: SWAN, the Study of Women's Health Across the Nation

Menopause. 2007 May-Jun;14(3 Pt 1):415-24. doi: 10.1097/gme.0b013e31802cc289.

Abstract

Objective: Women approaching menopause often ask their doctors, "When are my periods going to end?" The objective of this study was to predict time to the final menstrual period (FMP).

Design: This multiethnic, observational cohort study, the Study of Women's Health Across the Nation, has been ongoing since 1996. Data collected from seven annual study visits were used. The community-based cohort from seven national sites included 3,302 white, African American, Hispanic, Chinese, and Japanese women aged 42 to 52 years at baseline with a uterus and at least one ovary, who were not pregnant or taking reproductive hormones, and had at least one menstrual period within the past 3 months at baseline. The time to the FMP was defined retrospectively after 12 months of amenorrhea. Uni- and multivariable Cox proportional hazard models, hazard ratios (HRs), and 95% CIs were computed for variables of interest.

Results: A total of 2,662 women, of whom 706 had an observed FMP, were included. Age, menstrual cycles that had become farther apart (HR = 2.56, 95% CI = 1.94-3.39) or more variable (HR = 1.79, 95% CI = 1.45-2.21), and current smoking (HR = 1.68, 95% CI = 1.35-2.08) were all associated with shorter time to the FMP. Higher (log) follicle-stimulating hormone (HR = 2.32, 95% CI = 2.02-2.67) was related to a shorter time to the FMP, but the highest estradiol category (>or=100 pg/mL [367 pmol/L]) was associated with an earlier onset of the FMP (HR = 2.16, 95% CI = 1.63-2.89). The number of vasomotor symptoms was related to an earlier FMP, whereas higher physical activity and educational levels were associated with a later FMP.

Conclusions: Age, menstrual cycle recall, smoking status, and hormone measurements can be used to estimate when the FMP will occur, allowing for more precise estimates for older midlife women: in the most extreme cases, ie, age 54, high estradiol level, current smoking, and high follicle-stimulating hormone level, the FMP can be estimated to within 1 year.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Age Factors
  • Asian People / statistics & numerical data
  • Black People / statistics & numerical data
  • Cohort Studies
  • Confidence Intervals
  • Cultural Characteristics
  • Ethnicity / statistics & numerical data*
  • Female
  • Health Behavior / ethnology*
  • Hispanic or Latino / statistics & numerical data
  • Humans
  • Longitudinal Studies
  • Menopause / ethnology*
  • Menopause / physiology
  • Menstrual Cycle / ethnology*
  • Menstrual Cycle / physiology
  • Middle Aged
  • Odds Ratio
  • Proportional Hazards Models
  • United States / epidemiology
  • White People / statistics & numerical data
  • Women's Health / ethnology*