Hot flashes get the attention, but the pattern of your periods is what tells you where you are in perimenopause. Your cycle is the diagnosis. Everything else is the symptom list.
When it starts and how long it lasts
Perimenopause runs from your first irregular cycles until one year after your final period. Median onset is age 47, the final period comes at 51 to 52, and the transition lasts four or more years at the median.
Starting earlier means spending longer in it. In a SWAN analysis, women in the earliest quartile of onset had a median transition of 8.6 years, against 4.3 years for the latest quartile.
Your cycle marks the stage
Two changes define the stages. In the early transition, consecutive cycles differ by 7 days or more, and that variability recurs within 10 cycles. In the late transition, you go 60 days or more without a period.
Because the staging rests on a pattern that only shows up over months, a calendar or an app tells me more than any single lab value. Track the start date of each period, how many days it lasts, and how heavy it is.
Hot flashes and night sweats
Up to 80% of women have them. A hot flash is a sudden intense heat through the face, neck and chest that lasts 1 to 5 minutes, sometimes with sweating, chills or a racing heartbeat. Night sweats are the same thing during sleep.
They last longer than most women expect. Among women with frequent hot flashes, meaning six or more days in a two-week stretch, the median was 7.4 years in total and 4.5 years after the final period. Duration varies by group: a median of 10.1 years in African American women, 8.9 in Hispanic women, 6.5 in non-Hispanic white women, 5.4 in Chinese women and 4.8 in Japanese women.
Sleep, mood and memory
Sleep problems are common in midlife. Estimates range from about 40% to over 60% of women during the transition. Night sweats fragment sleep, and depression, restless legs and sleep apnea all become more common at this age as well. These overlap more often than they occur alone, so I screen for each of them, and I refer you for a sleep study when the pattern points there.
Depression risk rises in this window. Women report at least double the rates of depression during the transition and the years just after, and some studies put it higher still. Your risk is greater if you have had depressed mood before.
Between 40% and 60% of midlife women report forgetfulness, trouble pulling up words and names, and difficulty focusing. These changes are typically mild and within the range of normal. Dementia at midlife is very rare, though a decline that keeps worsening or interferes with your work should be evaluated rather than attributed to perimenopause.
Vaginal, urinary and sexual changes
Dryness, pain with sex and urinary symptoms are grouped as genitourinary syndrome of menopause. Pain with sex often rises early in the transition, while a drop in desire tends to come later. Many women do not notice these changes until years after their periods stop.
Estrogen swings can also worsen hormone-related headaches. Most of these migraines settle after menopause, though some do not.
Why a hormone test usually will not answer the question
FSH climbs and falls through the transition, so a single value can mislead. It is often elevated before your cycles become irregular, sometimes years before, and in the late transition it may read in the menopausal range or the reproductive range depending on the day it is drawn. For that reason, checking FSH is not routinely recommended to establish whether you are perimenopausal, and your menstrual history remains the better tool.
AMH is a blood test that reflects how many eggs remain in your ovaries, and it falls as you approach menopause. A very low level suggests your final period may come within the next year or two. A higher level makes it unlikely in the next year. It cannot pin down a date, though, and it is less accurate before your late 40s. Birth control pills can make the result falsely low. For these reasons, AMH is not a routine test for diagnosing perimenopause. Your age and cycle pattern remain the best guides
Testing does earn its place in two situations: if you are under 40, because early ovarian insufficiency changes what we do, and if you have had a hysterectomy or an endometrial ablation, because there is no cycle left to stage you by, and even then a single draw can be ambiguous, so it usually takes more than one.
Bleeding that should be evaluated
Heavier bleeding should not be written off as just perimenopause. Cycles without ovulation can make bleeding heavy on their own, and fibroids, polyps and endometrial changes all become more common at this age. Both can be true at the same time, which is why heavy bleeding gets evaluated rather than waited out.
These bleeding patterns are not normal and need to be evaluated: changing a pad or tampon at least every hour, periods lasting longer than 8 days, bleeding between periods, bleeding after sex, cycles consistently shorter than 24 days, or any bleeding at all after a full year without a period. That last one should be looked at promptly rather than watched.
At 45 or older, abnormal bleeding requires further workup, often including ultrasound imaging and endometrial sampling (biopsy). It is not something to put off while waiting to see whether the bleeding settles.
You can still get pregnant
You can still get pregnant in perimenopause, even when your cycles are irregular. If you do not want a pregnancy, use birth control until a full year has passed since your last period.
What to bring to your visit
I can stage where you are and sort out which symptoms are worth treating in one visit. Bring three months of tracked cycles, a list of your symptoms with a note on which ones interfere with your work or sleep, and your family history of breast cancer, blood clots and heart disease.
If your symptoms are bothersome and you want to know whether treatment fits, hormone therapy in perimenopause is covered here.
Summary:
Track every cycle: start date, length, flow
Note which symptoms interfere with work or sleep
Bring your family history of breast cancer, blood clots and heart disease
Keep using birth control until one year past your last period
Get heavy, prolonged, between-period or post-sex bleeding evaluated by your gynecologist, along with any bleeding after a year without a period
To talk through where you are and what to do about it, use the Schedule Today button at the top of this page, call or text (513) 960-5360, or email info@myprecisionendo.com. Membership details are on our pricing page.
Allison Johns, MD
