What Are the Stages of Menopause?
The STRAW+10 staging system explained: what marks each stage of reproductive aging and how long each one lasts.
Short answer
Scientists divide reproductive aging into stages using a system called STRAW+10, published in 2012. The main stages are the late reproductive years, the early and late menopausal transition, and early and late postmenopause. Menopause itself is a single moment, the final menstrual period, confirmed only after 12 months without a period. The late transition lasts 1 to 3 years on average, and early postmenopause about 5 to 8 years. The earlier stages vary in length from woman to woman.
A young science
Women have always gone through menopause, but science described its stages only recently. The first formal staging system, called STRAW, was agreed at a workshop in Park City, Utah, in 2001.[1] Ten years later, researchers revised it with new evidence, much of it from long-term studies that followed women through midlife. The revised system, STRAW+10, was published in 2012.[2] One of the largest of those studies, the Study of Women's Health Across the Nation (SWAN), began in 1996 and enrolled 3,302 women at seven sites across the United States.[3] Formal staging dates only from 2001, and researchers are still adding to the picture.
The stages at a glance
STRAW+10 numbers each stage around the final menstrual period, which is stage 0. Negative numbers come before it and positive numbers come after it.[2] The early and peak reproductive years (stages -5 and -4) come before the stages shown here.
| Stage | Name | What marks it | Typical length |
|---|---|---|---|
| -3b | Late reproductive | Regular cycles; AMH and antral follicle count are low | Variable |
| -3a | Late reproductive | Subtle changes in flow or cycle length; FSH begins to vary | Variable |
| -2 | Early menopausal transition | Cycle length varies by 7 days or more, again and again | Variable |
| -1 | Late menopausal transition | 60 days or more without a period | 1 to 3 years |
| 0 | Final menstrual period | Confirmed after 12 months without a period | A single point |
| +1a, +1b | Early postmenopause | The first two years after the final period | About 1 year each |
| +1c | Early postmenopause | Hormone levels stabilize | 3 to 6 years |
| +2 | Late postmenopause | Urogenital symptoms become more common | Remaining lifespan |
Where perimenopause fits
"Perimenopause" is the everyday name for the years around the final period. In STRAW+10, it begins with the early menopausal transition (stage -2) and ends 12 months after the final menstrual period.[2]
What happens in each stage
- Late reproductive years. Cycles are still regular, but AMH and antral follicle count are already low. Later in this stage, cycles may become shorter and early-cycle FSH starts to rise and vary.[2]
- Early menopausal transition. The length of consecutive cycles differs by 7 days or more, and this keeps happening within 10 cycles of the first change.[2]
- Late menopausal transition. Gaps of 60 days or more between periods appear. A random FSH level above 25 IU/L is typical, and hot flashes and night sweats are likely.[2]
- Early postmenopause. Hot flashes and night sweats are most likely in the first two years after the final period. Over the next 3 to 6 years, hormone levels settle.[2]
- Late postmenopause. Vaginal dryness and other urogenital symptoms become increasingly common.[2]
Why the stages follow periods, not a blood test
STRAW+10 uses the pattern of menstrual bleeding as the main criterion. Hormone levels and ultrasound counts are supporting evidence, partly because laboratory tests for these markers are not standardized internationally. Hormone levels also swing widely in the late transition.[2]
The system applies regardless of age, ethnicity, body size or lifestyle. Bleeding criteria do not apply with polycystic ovary syndrome or hypothalamic amenorrhea, or after a hysterectomy or endometrial ablation. After a hysterectomy or ablation, clinicians use the supporting markers instead.[2]
What researchers are still working out
STRAW+10 can give typical lengths for the later stages, but the earlier stages are listed as "variable". Women move through them at very different speeds. In SWAN, the median length of the whole transition ranged from about 4.4 years in women who started it latest to about 8.6 years in women who started it earliest.[4]
Knowing in advance when one woman will reach the transition is an open scientific question. It is the question LifeAhead works on: forecasting the approximate timing of the menopausal transition, with a prediction interval, for clinicians to use in counseling. Read about the science.
Related reading
References
- Soules MR, Sherman S, Parrott E, et al. Executive summary: Stages of Reproductive Aging Workshop (STRAW). Fertil Steril. 2001;76(5):874-878. doi:10.1016/s0015-0282(01)02909-0
- Harlow SD, Gass M, Hall JE, et al. Executive summary of the Stages of Reproductive Aging Workshop + 10: addressing the unfinished agenda of staging reproductive aging. J Clin Endocrinol Metab. 2012;97(4):1159-1168. doi:10.1210/jc.2011-3362
- El Khoudary SR, Greendale G, Crawford SL, et al. The menopause transition and women's health at midlife: a progress report from the Study of Women's Health Across the Nation (SWAN). Menopause. 2019;26(10):1213-1227. doi:10.1097/GME.0000000000001424
- Paramsothy P, Harlow SD, Nan B, et al. Duration of the menopausal transition is longer in women with young age at onset: the multiethnic Study of Women's Health Across the Nation. Menopause. 2017;24(2):142-149. doi:10.1097/GME.0000000000000736
This article is for general education and does not replace advice from your healthcare provider.
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