Defining Premenopause, Perimenopause, and Menopause

Menopause, premenopause, and perimenopause refer to specific stages in a person's fertility cycle during and at the end of their child-bearing years.

There are a wide range of fluctuations in hormones from adolescence, at the beginning of the menstrual cycle (monthly period), to the fertility peak in the mid-20s and then toward menopause. Perimenopause usually occurs in your 40s and menopause at an average age of 51, but the actual timeframe can vary from person to person.

This article explains these different terms and the symptoms most often associated with the stage. It will help you to understand why you may be experiencing early menopause or why missed periods may be a sign that you need to see a healthcare provider for a different medical issue.

Menopause

Menopause usually occurs between the ages of 45 and 55, but for some people, menopause can happen as early as the 30s or 40s. For others, menopause may not occur until they reach age 60.

In the United States, the average age is at 51, with a menopause phase lasting two years.

Under normal circumstances, you do not suddenly experience menopause. Instead, it occurs gradually and involves different phases.

Perimenopause

Perimenopause usually occurs during the 40s. The most significant sign that someone is in the perimenopausal phase of the reproductive cycle is that they have visible symptoms.

These symptoms occur due to the decrease in estrogen and other sex hormones. Some healthcare providers may refer to this phase as "menopause transition." Common signs and symptoms of perimenopause may include:

• Irregular and/or abnormal periods (that may be heavier or lighter in flow)
• Hot flashes
• Night sweats
• Breast tenderness
• Increase in weight gain
• Worsening symptoms of PMS (before periods begin)
• Thinning of hair
• Constipation
• Lower sex drive (or loss of sex drive) and/or vaginal dryness
• Headaches and/or muscle aches
• Problems with mood, memory, or concentration
• Tachycardia (an increase in heart rate)
• An increased incidence of urinary tract infections (due to hormonal changes that cause thinning of the urethra)
• Problems conceiving (in people trying to have a baby)

These physical and emotional symptoms (such as hot flashes and mood swings) may continue into full menopause. It’s also important to note that during perimenopause a person can still get pregnant, but it will probably be more difficult than when they were younger.

Premenopause

This phase does not involve any of the classic signs or symptoms of menopause (such as night sweats, insomnia, or missed periods). A person experiencing premenopause has periods that may or may not be regular, and they are still considered fertile in the reproductive phase of life. 

Early Menopause

Some people experience menopause earlier than in their 40s, perhaps even before their 30s. The age you were when your periods started has no effect on when the perimenopausal phase starts.

However, perimenopause and menopause can be influenced by several factors, including:

• A history of smoking
  
• Genetics (maternal history of early menopause)
• Chromosome defects
• Autoimmune diseases
• Hysterectomy (removal of the ovaries)
• Chemotherapy (or other cancer treatments)

What Is Amenorrhea?

Amenorrhea simply means the absence of monthly periods. There are several reasons that amenorrhea may occur when it is not linked with menopause or perimenopause. 

There are several reasons that amenorrhea can occur, including:

• Thyroid problems
• Suddenly stopping birth control
• Ovulation absence, most commonly due to pregnancy (other causes include sudden weight loss, overexercise, and eating disorders)
• Severe stress
• Obesity (being overweight)
• Other medical conditions, such as pituitary tumors or polycystic ovary syndrome (PCOS)
• Premature ovarian insufficiency (POI), a condition that may involve some of the same symptoms of perimenopause, such as hot flashes, but it occurs due to an unknown cause

Summary

Terms that describe menopause fall on a continuum across the reproductive years. They provide a timeline that occurs from the first menstrual period—when it's possible to conceive—to the time when the ovaries produce less estrogen and ovulation has come to a halt, called menopause. 

Premenopause and perimenopause are terms that describe stages that occur at or approaching menopause. You may not have symptoms with premenopause, although hormonal changes may be at work for several years. Perimenopause often involves the same type of symptoms seen with menopause.

If you are experiencing reproductive changes, be sure to consult your healthcare provider for an accurate diagnosis of what's causing a missed period or more frequent urinary tract infections.