Change in Follicle-Stimulating Hormone and Estradiol Across the Menopausal Transition: Effect of Age at the Final Menstrual Period

TLDR

To determine whether patterns of change in serum estradiol (E2) and follicle‑stimulating hormone (FSH) across the menopausal transition were associated with age at the final menstrual period (FMP). The Study of Women’s Health Across the Nation (SWAN) followed 3,302 multiethnic women aged 42–52 at baseline, annually assaying serum E2 and FSH and using semiparametric stochastic and piecewise linear mixed models to evaluate hormone change patterns in 1,215 women with a documented natural FMP by 2006. FSH rose beginning 6.1 yr before FMP, accelerated 2.05 yr before, decelerated 0.2 yr before, and stabilized 2 yr after, independent of age, race/ethnicity, or smoking, while obesity delayed the rise and attenuated the increase; E2 remained stable until 2.03 yr before FMP, then declined, peaking at the FMP and stabilizing 2.17 yr after, with obesity, smoking, and East Asian ethnicity affecting levels but not the overall pattern, indicating that time spans—not patterns—of hormone change are linked to obesity and race/ethnicity but not age at FMP.

Abstract

Background and Objective: To determine whether patterns of change in serum estradiol (E2) and FSH across the menopausal transition were associated with age at the final menstrual period (FMP). Design and Setting: The Study of Women's Health Across the Nation (SWAN) is a seven-site, multiethnic, longitudinal study of the menopausal transition being conducted in 3302 menstruating women who were aged 42–52 yr at the 1996 study baseline. Measurements: Annually collected serum was assayed for E2 and FSH levels. Patterns of hormone change were evaluated in the 1215 women with a documented natural FMP by follow-up visit 9 (2006) using semiparametric stochastic and piecewise linear mixed modeling. Results: The FSH pattern across the menopausal transition began with an increase 6.10 yr before the FMP, an acceleration 2.05 yr before the FMP, deceleration beginning 0.20 yr before the FMP, and attainment of stable levels 2.00 yr after the FMP, independent of age at the FMP, race/ethnicity, or smoking status. Obesity attenuated the FSH rise and delayed the initial increase to 5.45 yr before the FMP. The mean E2 concentration did not change until 2.03 yr before the FMP when it began decreasing, achieving maximal rate of change at the FMP, then decelerating to achieve stability 2.17 yr after the FMP. Obesity, smoking behavior, and being Chinese or Japanese were associated with some variation in E2 levels but not the pattern of E2 change. Conclusions: Time spans and overall patterns of change in serum FSH and E2 across the menopausal transition were not related to age at FMP or smoking, whereas time spans but not overall patterns were related to obesity and race/ethnicity.