A primer on perimenopause

What to expect in the years leading up to your last period.
(Credit: iStock/Getty Images)

Perimenopause is a stage every biological woman will go through in her lifetime. It's a process that some of us dread and some of us look forward to (no more periods, hurrah!). Here are some essential facts and answers to common questions to help you understand what to expect in the future — or help you make sense of what's going on with your body right now.

What is it?

Simply put, perimenopause — or the menopausal transition — happens when the number and quality of eggs in your ovaries reach a tipping point. All women are born with about two million eggs, which live in homes called follicles. Each month, around 1,000 eggs naturally die off as one matures and leaves the nest during ovulation.

Through your reproductive years, your body's genetic repair crew keeps your remaining eggs and their homes in well-appointed, fertility-ready shape. As you age, however, your body's budget for egg renovation gets depleted, meaning a gradual decline in the functionality of your eggs.

By the time you hit menopause, none of your eggs remain viable. This results in a decrease of estrogen and progesterone, and leads to those much-discussed symptoms of hot flushes (also known as hot flashes), vaginal dryness and mood swings.

When does it happen?

On average, perimenopause begins about four years before your last period, or around age 47, but can begin up to 10 years prior to that.

What are the stages?

One clue that you're in your late reproductive years is that your menstrual cycles start to shorten. For example, instead of having a period every 25 to 35 days, you may notice they happen every 21 to 31 days.

But once you hit the early stage of perimenopause, your cycles typically start to lengthen to around 40 to 50 days. During the late stage of perimenopause, which usually lasts one to three years, periods become even less frequent and other perimenopausal symptoms often start to kick in.

Not all women experience the same bleeding pattern during the stages of transition. Many will have fairly regular but less frequent cycles with lighter bleeding, while others will go through long periods of amenorrhea (no periods) with bursts of short ovulatory cycles. The take-home message is that a change in your menstrual cycles should generally clue you in that the transition is impending.

Typical symptoms — and when to worry

Although many of us know of a unicorn friend of a friend whose journey into menopause was seamless and pleasant, the vast majority of women experience perimenopausal symptoms. Here are some of the most common.

1. Hot flushes:

By far the most common hallmark of perimenopause, hot flushes occur in up to 80 per cent of women. A hot flush usually starts in the face or chest, then rapidly radiates out to the rest of the body, accompanied by sweating and sometimes chills and palpitations. Lasting two to four minutes on average, they can occur anywhere from once or twice a day to once an hour. They are particularly common at night.

Watch out for: Medical conditions such as hyperthyroidism, infections or reactions to medications can also cause hot flush–like symptoms. Seek medical attention if you notice other symptoms accompanying flushing, including weight loss, a persistent feverish feeling or unduly low energy.

2. Irregular periods:

As mentioned above, a wide range of changes to your menstrual cycle can occur during perimenopause.

Watch out for: Though endometrial cancer — which can cause irregular, heavier bleeding — typically affects postmenopausal women, it can also crop up earlier. If your periods are lasting longer than seven days or are accompanied by new, severe cramping and bleeding, see your health-care provider.

3. Insomnia:

Close to 50 per cent of women experience sleep disturbances during the transition. A host of different factors can induce sleeplessness, including sheet-drenching hot flushes and hormonal changes that may worsen anxiety and depression.

Watch out for: A certain degree of sleep and emotional changes are normal, but book an appointment with your doctor if your symptoms are causing problems with daytime functioning at home or work, or are affecting your relationships.

4. Vaginal dryness:

Estrogen helps keep the vulva and vagina plump and lubricated, but during perimenopause estrogen levels start to drop, which thins surface tissues and can lead to itching, dryness and painful sex.

Watch out for: Yeast infections and sexually transmitted infections also strike perimenopausal women, so don't immediately assume your symptoms are due to the transition — especially if you have a change in discharge or a new partner. Also, don't hesitate to see a medical professional if your symptoms are affecting your quality of life, as there are safe and effective treatments.

Top FAQs, answered:

1. Can I still get pregnant during perimenopause?

Although the chances of spontaneous conception are very low, as long as you're ovulating there's still a possibility that you could get pregnant. Consider yourself out of the woods baby-wise when you haven't had a period for at least 12 months, which signals the start of menopause itself.

2. If I'm on birth control, will I know if I'm perimenopausal?

The short answer is that you probably won't. Taking the birth control pill provides your body with regular cycles of estrogen and progesterone, which simulate the effects of ovulation, induce regular periods and stave off the symptoms of perimenopause. If you're over 50, consider stopping the pill and using a non-hormonal form of contraception for a few months to see what happens.

3. Are there any effective natural or herbal treatments for perimenopausal symptoms?

Although up to 75 per cent of women turn to complementary and alternative therapies during the transition, plant-based supplements like black cohosh, red clover and primrose oil have either mixed or minimal evidence for benefit.

Compounded bioidentical hormones, while endorsed by some alternative health-care practitioners and celebrities, are not recommended by most physicians due to major concerns about their safety and efficacy.

A better bet would be to focus on lifestyle management: avoid hot-flush triggers such as hot and spicy foods, alcohol, caffeine, warm environments and stress, and focus on mindfulness, exercise and sleep to improve mood symptoms.

More cause for pause

Aside from the changes happening with our bodies, for many, perimenopause is accompanied by mixed feelings about other life and identity transitions. These may include the end of one's baby-bearing years, children leaving home and the approach of older age.

We can take comfort, however, in the fact that this process is part of our unique life experience as women that has been experienced by many before us — who have all emerged hot-flush and period-free on the other side. So here's to our salad days, our golden years and everything in between.

Dr. Melissa Lem is a well-travelled family doctor, on-air medical expert and clinical instructor at the University of British Columbia. Follow her tweets about health, nature and the environment @Melissa_Lem.


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