Perimenopause periods: flooding, skipping and everything between

In the SOGC’s words, perimenopause is “the transitional phase leading up to menopause”. Perimenopause is a stage, not an age. It does not start at the same age for everyone. During these years, periods can change in ways that surprise people who once knew their cycle well. This Column is for everyone who reaches this stage, whatever their gender, and for anyone beside them.

What perimenopause is, in the SOGC’s words

The SOGC says perimenopause “can occur anywhere from 4 – 8 years before the menopause and in some it can be 10 years or longer”. Menopause itself is confirmed after “12 consecutive months without a menstrual period”. The SOGC notes this definition doesn’t apply when periods stop for other reasons, such as a hysterectomy, a hormonal IUD or hormonal birth control. The average age of menopause in Canada is 51, and it “typically ranges between 45 – 55 years”. That is an average for menopause. It is not a start date for perimenopause.

The SOGC adds one more line: “Pregnancy is still possible during this stage therefore contraception may be needed.” So a late period in these years is not always a sign of perimenopause.

Skipping, flooding and everything between

Here is how the sources describe periods in perimenopause, each in its own words.

The SOGC: “Women may experience irregular menstrual cycles that may include skipped periods, shorter cycles, or unusually heavy or light bleeding.”

The NHS: periods “may happen more often or less often, and bleeding may get heavier or lighter”.

HealthLink BC: “heavier or lighter blood flows and shorter or longer cycles”.

UBC’s Centre for Menstrual Cycle and Ovulation Research (CeMCOR) adds a figure from its own research: “Early in perimenopause when cycles are regular, approximately 25% of women will have at least one heavy period.” That is one research centre’s figure.

“Flooding” is an everyday word for a sudden, very heavy flow; CeMCOR puts it in quotation marks beside “what doctors call menorrhagia”. In forums, people describe periods arriving months apart and then twice in a row, and bleeding through onto a car seat. Those are readers’ descriptions, not a measure of what is typical.

A note on words: some sources we cite here say “women”. We keep researchers’ words so we report their findings accurately. The Reading Room is for everyone who menstruates.

When heavier periods are worth a call

The sources describe changing periods in this stage. The NHS also says to see a GP if “you still have periods but your bleeding pattern has changed and you’re bleeding more, not less, than before”.

The SOGC’s general list of heavy-bleeding signs, in its words:

• “Bleeding that lasts more than 7 days.”
• “Bleeding that soaks through one or more tampons or pads every hour for several hours in a row.”
• “Needing to wear more than one pad at a time to control menstrual flow.”
• “Needing to change pads or tampons during the night.”
• “Menstrual flow with blood clots that are as big as a quarter or larger.”

CeMCOR says that feeling “faint or dizzy when you stand up” is “a reason to make an emergency doctor appointment”. In an emergency, call 9-1-1.

For more on heavy periods, see “How heavy is heavy? Reading your own flow”.

This is where the Editor stops and a healthcare provider begins.

More than periods

Periods are one part of this stage. The Menopause Foundation of Canada counts “more than 30 symptoms associated with perimenopause and menopause”. Its report (October 2023) on a Leger survey of 1,023 Canadian women aged 40 to 60, conducted in August 2022, found that 95% reported an average of seven symptoms and 46% said they felt unprepared for menopause. The Foundation’s pages the Editor read do not discuss periods, so this Column quotes it only for these figures.

What each format offers when periods get unpredictable

What follows describes each format, in the house’s fixed order. It is not a ranking, and no format is made “for perimenopause”. Two people at the same stage choose differently, and both are right.

Period pads & liners. Liners are sold for light days and spotting. Larger and “overnight” disposable period pads come in each maker’s own sizes. In Canada, those size words have no absorbency standard behind them. The package and the maker’s instructions say what each size means.

Tampons. Tampons carry Health Canada’s absorbency words, from Light to Ultra. Health Canada says: “Use the lowest absorbency that will meet your needs.” It also says: “Change your tampon every 4 to 8 hours, and do not use tampons overnight.”

Cups. Cups collect period blood rather than absorb it. Follow the maker’s instructions for how long to wear it.

Discs. Discs also collect rather than absorb. As with cups, follow the maker’s instructions for how long to wear it. They are worth reading before a heavy or unpredictable day.

Period underwear. Period underwear is worn in place of regular underwear. Its absorbency is described in each maker’s own units. The maker’s label and instructions say how long each style is meant to be worn.

Reusable period pads. Reusable period pads are washed and worn again. They come in sizes and absorbencies set by each maker. As with disposable period pads, the words on the label are the maker’s, and the maker’s instructions say how to wash them.

Comfort & care. Some people keep practical items for unpredictable days: a wet bag or carry pouch for used products, and bed protection for nights. These are household items, not treatments.

The SOGC lists bladder leaks (“stress incontinence”) among the changes some people notice around menopause. Incontinence pads and period pads are built for different liquids; that difference has its own Column, “Incontinence pads and period pads: what’s the difference?”.

Being ready for surprises

When the calendar stops helping, people describe planning around it instead. Some keep spare underwear, a change of clothes and supplies in a bag, a car or a locker. Some track their periods on a paper calendar or in an app. If you use an app, read how it stores your information. CeMCOR offers a Daily Perimenopause Diary for recording flow. A written record can be useful to bring to an appointment.

What this is not

This Column reported what named health sources say about periods in perimenopause, and described each format. It cannot tell you whether you are in perimenopause, or why your periods have changed. It did not compare brands or rank formats. It makes no claim that any product manages flooding or brings menopause relief.