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Could I be in Perimenopause?


I’m noticing some peculiar changes—sore breasts, sleep problems and heavier flow, sometimes with clots. I’m 43, my period is still regular - could I be starting menopause?


Thank you for your question—it’s a common one today because 19-20 percent of all Canadian women are between ages 35 and 55. Perimenopause happens during these ages.

First, I need to define some confusing terms. We have used the word “menopause” to mean everything that’s changing in midlife women, as well as to indicate the final menstrual flow. Now days, “menopause” is used specifically to mean that a year has passed since your final menstrual flow. “Perimenopause,” what I think you meant to ask about, means the years of change before menopause.

The answer to your question is—Yes, you sound like you’re in Phase A of Perimenopause (1;2). This is the first of five Phases before you graduate into the calm of menopause!

The five phases of perimenopause

We now know that estrogen levels rise in our late thirties and become erratically high through most of perimenopause. Eventually, higher estrogen levels along with lower progesterone levels cause symptoms like breast swelling, soreness and lumpiness. These hormonal changes, especially if you don’t ovulate, can also cause heavier or longer flow, and premenstrual mood, fluid and appetite changes. Some women get migraines for the first time. Others start waking in the middle of the night for no reason and then toss and turn until daylight—this makes for very difficult, tired days at work.

At some point, about twenty to thirty percent of us, while we’re still having regular periods, start getting night sweats. Commonly these sweats happen in the wee hours of the night before or during flow (3). Others will have such heavy flow with cramps and clots that they become anemic.

I’m sure you are wondering what most women want to know—when will perimenopause end? That’s highly variable and different for every woman. But the diagram above gives you some markers so you can see your progress. There are two times for which we have firm averages—it is one year from the final menstrual flow until menopause (Phase E); it is four years on average from the onset of irregular flow in Phase C to menopause (4;5). However, no one says we all go from A to E without variability. You can start having irregular periods and then go back to regular ones, or even skip periods and then again have regular flow for more months (6).

So, back to you and your regular flow but noticeable changes. Although some of these changes are mysterious—like waking in mid-sleep. Higher estrogen levels cause other changes, such as sore breasts and more days of stretchy mucus. The heavier flow is likely due to the higher estrogen associated with less progesterone (7). Keeping a Daily Perimenopause Diary will help you understand and cope with these changes.

To briefly look forward in perimenopausePhase B is much like A except that here daytime hot flushes may start and menstrual cycles are shortest of all (may be down to 24-25 days between periods). Women who develop disturbing hot flushes in later phases of perimenopause are likely to have significant premenstrual breast, fluid and mood changes during Phases A and B (8).

Phase C of Perimenopause starts when periods become irregular, such as alternating a short one and a longer one. At the shift from regular to irregular cycles, many women have at least one episode of flooding menstruation (9). Just so you know, a number of experts believe that the “menopausal transition,” another name for this time of life, begins with irregular flow (10). I’m afraid, even though you and I know better, those experts would tell you that you couldn’t possibly be in perimenopause because your periods are still regular!

Phase D of Perimenopause begins with your first skipped period (usually this means about two months without flow). By this time, sore breasts are getting better, and if they occur, you will know a period is about to start. Make sure to record your flow on a calendar or the Daily Perimenopause Diary so that you can start the one-year clock for Phase E and your final menstrual flow.

If you’d like to learn more about perimenopause and its phases, you will be interested in the book we’ve just published called Transitions Through the Perimenopausal Years. It is a practical handbook about perimenopause that is available in paperback.  
In summary, you are definitely in the earliest phase of perimenopause. I believe that most of us can cope with the changing and sometimes unpleasant experiences of perimenopause if we can track our progress and we know that this will eventually end in the calm and confidence of menopause.

Hope this is helpful for you.


Reference List

1. Prior JC 1998 Perimenopause: The complex endocrinology of the menopausal transition. Endocr Rev 19:397-428

2. Prior JC 2002 The ageing female reproductive axis II: ovulatory changes with perimenopause. In: Chadwick DJ, Goode JA (eds) Endocrine Facets of Ageing.John Wiley and Sons Ltd, Chichester, UK172-186

3. Hale GE, Hitchcock CL, Williams LA, Vigna YM, Prior JC 2003 Cyclicity of breast tenderness and night-time vasomotor symptoms in mid-life women: information collected using the Daily Perimenopause Diary. Climacteric 6:128-139

4. Dudley EC, Hopper JL, Taffe J, Guthrie JR, Burger HG, Dennerstein L 1998 Using longitudinal data to define the perimenopause by menstrual cycle characteristics. Climacteric 1:1-8

5. McKinlay SM, Brambilla DJ, Posner JG 1992 The normal menopause transition. Maturitas 14:103-115

6. Mansfield PK, Carey M, Anderson A, Barsom SH, Koch PB 2004 Staging the menopausal transition: data from the TREMIN Research Program on Women's Health. Womens Health Issues 14:220-226

7. Moen MH, Kahn H, Bjerve KS, Halvorsen TB 2004 Menometrorrhagia in the perimenopause is associated with increased serum estradiol. Maturitas 47:151-155

8. Morse CA, Dudley E, Guthrie J, Dennerstein L 1989 Relationships between premenstrual complaints and perimenopausal experiences. Journal of Psychosomatic Obstetrics and Gynecology 19:182-191

9. Kaufert PA, Gilbert P, Tate R 1987 Defining menopausal status: the impact of longitudinal data. Maturitas 9:217-226

10. Soules MR, Sherman S, Parrott E, Rebar R, Santoro N, Utian W, Woods N 2001 Executive summary: stages of reproductive aging workshop (STRAW). Fertil Steril 76:874-878


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Updated Date: 
Tuesday, November 19, 2013 - 13:30

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