How Age and Other Factors Affect Perimenopause

Perimenopause is the transitional phase leading up to menopause, which marks 12 months since your last menstrual cycle. During perimenopause, the body is making less of the hormone estrogen, and this can cause perimenopausal symptoms like menstrual pattern changes, hot flashes, mood swings, and vaginal dryness.

Perimenopause commonly starts when you're in your late 40s, but some people start noticing changes as early as their mid-30s.

When you enter perimenopause will be based on several factors, such as genetics, medical conditions, lifestyle, and overall health.

Body Changes

Perimenopause signals the reversal of the reproductive process that began during puberty.

This life phase marks the start of the natural decline of two hormones—estrogen and progesterone—that play key roles in the reproductive system. They also support other bodily functions, such as mood regulation.

Throughout perimenopause, your body goes through many changes. During the transition, your body will:

• Release eggs (ovulate) less regularly 
• Produce less estrogen and progesterone
• Become less fertile
• Have irregular menstrual cycles (shorter or longer, heavier or lighter, depending on hormone levels)

The earlier stages of perimenopause are associated with fluctuating estrogen levels and shorter menstrual cycles, while the later stages of perimenopause are characterized by declining estrogen levels and missed periods, along with other symptoms.

Symptoms

With changing estrogen levels and other hormonal shifts in the body during perimenopause, it's typical to experience symptoms like hot flashes, mood swings, and period changes.

While not every person will experience perimenopause in the exact same way, there are a few common symptoms that many people notice during this transition, including:

• Menstrual cycle changes: Your periods might become unpredictable (shorter, longer, heavier, or lighter) during this time. Some months, you may not have a period at all.
• Hot flashes and night sweats: A sudden feeling of heat in your chest area and face is one of the most common perimenopausal symptoms. Hot flashes can range from a minor annoyance to a debilitating experience. When hot flashes occur during sleep, they're known as night sweats.
• Vaginal dryness: Lower estrogen levels can affect vaginal lubrication, causing dryness and pain in the vagina.
• Mood swings and depression: Fluctuating hormone levels during perimenopause can alter the brain chemicals that play a direct role in regulating your mood. Some people might be more at risk for depression during the menopausal transition due to a combination of hormonal and psychological factors.

Some perimenopausal symptoms are easy to spot, but there are also some changes that go on behind the scenes that you may not immediately link to perimenopause, including:

• Decreased bone density: Lowered estrogen levels can lead to bone loss, which can eventually develop into osteoporosis (a condition that causes bones to become thin and more easily breakable).
• Migraines: Some studies suggest that migraines may increase or start during perimenopause, likely related to factors like hormonal fluctuations, menstrual changes, and disrupted sleep.
• Sleep problems: Hormonal changes during perimenopause may prompt disruptions to your sleep cycle, such as trouble falling asleep or waking up during the night.
• Muscle and joint pain: Estrogen helps to reduce inflammation. As it declines, aches and pains can become more noticeable.
• Weight gain: A combination of hormonal and lifestyle changes that often occur during middle age can lead to a decrease in your physical activity levels and metabolism, which, in turn, can contribute to weight gain.
• Urinary tract infections (UTIs) and urinary incontinence: Decreased estrogen levels can cause thinning of the urethra and urinary tract, making you more susceptible to UTIs and urinary leaking.

Perimenopausal symptoms are expected and typical, but you should talk to your doctor if you have any questions or concerns—especially if your symptoms are interfering with your everyday life.

Your doctor can confirm that perimenopause is causing your symptoms—and not an underlying medical condition—and offer guidance on how to treat them.

Factors That Affect Onset

Just like puberty, perimenopause begins at different times for everyone. Most people enter perimenopause in their late 40s and reach the point of menopause in four years. However, the transition can start as early as your mid-30s or last for up to a decade.

There are many factors that influence the timing of earlier-than-usual perimenopausal onset—from genetics to health conditions to lifestyle habits.

• Genetics: If there’s no clear reason for starting perimenopause earlier than is typical, it's probably genetic. For example, the time that your mother started the transition to menopause can provide you with clues about when you might expect to start. Also consider how old you were when you started getting your period. Typically, the earlier you start to menstruate, the earlier you'll go through menopause.
• Medical conditions: Certain autoimmune diseases like rheumatoid arthritis (RA) or thyroid disease may contribute to an earlier onset of perimenopause. Epilepsy is a condition that comes with a risk of premature ovarian failure, which leads to earlier perimenopause.
• Lifestyle factors: Smoking has antiestrogenic effects that can contribute to early perimenopause. Having a lower body mass index (BMI) can also make for an earlier transition. Some studies also point to diet, exercise, and sun exposure as early-onset factors, though more research is needed to confirm the links.

People who have undergone certain medical treatments to remove or cause the ovaries to stop working (including a hysterectomy with oopherectomy, or removal of the ovaries, chemotherapy, or radiation) will bypass perimenopause and enter what's known as forced (surgical or medical) menopause.

A Word From Verywell

No matter at what age you enter perimenopause, the changes your body goes through can feel a little scary, uncomfortable, and anxiety-provoking. Remember that you're not alone. Chances are people you know are going through or have already gone through perimenopause.

While friends and family can be a much-needed source of support, you can also lean on your doctor or other healthcare professionals for direction. Feel free to ask them for advice regarding the emotional and physical changes you are going through during this transition.