What is perimenopause?

The phases of a woman’s reproductive life

Perimenopause is similar to puberty, but in reverse.  Whereas puberty is the phase women go through as their ovaries ramp up to create monthly ovulation, perimenopause is when this process winds down.  When perimenopause starts, the number of remaining eggs has decreased from several hundred thousand to several thousand.  Then this number decreases rapidly over the ensuing five to six years.  In essence, perimenopause is the life phase where fertility dramatically declines.  The perimenopausal transition can start anywhere from three to eight years (or more) before menopause.  The end of this decline marks menopause, the time when there are no further eggs remaining in the ovaries.  The phase beyond menopause is referred to as the postmenopause.

A layer of cells that surrounds each egg, called follicular cells, produce the female hormones, which are estrogen and progesterone.  Prior to puberty, the eggs and follicular cells lay dormant.  After puberty, the eggs start maturing and the follicular cells produce large amounts of our female hormones. When a woman enters perimenopause, there are fewer eggs and less hormones being produced.  At this point the ovaries no longer release an egg on a regular monthly cycle.  Sometime an egg is not released at all, which leads to a missed a menstrual period.  Since hormone production is tied to ovulation, the hormone levels would be particularly low when this happens.  However, during other months, ovulation and a rise in hormone levels will occur.  When eggs are released in such a disorganized fashion, estrogen and progesterone are no longer in balance and this leads to unpredictable symptoms that come and go and change from month to month.

How do you know if you are in perimenopause?

Women can anticipate that perimenopause will appear sometime is their 40’s.  Since the average age at menopause is 52, the average age of the onset of perimenopause is 47.  However, since natural menopause can occur anytime between ages 45 and 55, the time of perimenopause will also vary.  Some women will encounter perimenopause in their late 30’s!

Perimenopause is characterized by the appearance of a change in the menstrual pattern.  One of the early things women will notice is a decrease in interval between periods.  This occurs because the ovary releases an egg earlier than normal.  Instead of the usual 28 or so days, the menstrual period arrives 2 to 3, or even more days earlier.  As time goes on, the interval can continue to decrease.

The next characteristic change of perimenopause is that an egg is not released at all.  This leads to an occasional missed menstrual period and so the interval between bleeding episodes stretches to 45-60 or more days.  Going this long without a period creates an increase in the buildup of the lining of the uterus, which then can cause an extremely heavy menstrual bleeding.  To add insult to injury, the imbalance of hormones also causes intermittent spotting between menses.

A number of other symptoms will appear that indicate a woman is in perimenopause.  These will be described in more detail below, but include hot flashes, sleep disturbance, and mood changes.  The onset of these symptoms would help alert women who have had a hysterectomy that they may be perimenopausal.

There are no reliable blood tests to diagnose perimenopause and so routine blood tests are not recommended.  Hormone changes definitely occur, but because they are so erratic, a blood test on any given day that measures the estrogen level is not very helpful.  In some situations measuring the follicle-stimulating hormone (FSH) or anti-Mullerian hormone (AMH) levels may be considered.  The FSH level fluctuates but if it is over 35 to 40, this suggests perimenopause.  The AMH level estimates how many eggs remain in the ovary and this test is used in fertility clinics to assess a woman’s likelihood of achieving pregnancy.  An AMH test can be a rough indicator of when a woman may expect to reach menopause.

What are typical symptoms of perimenopause?

The brain is one of the organs most severely impacted by the hormone changes that occur in perimenopause.  The decline in estrogen, as well as the rise and fall of other various hormones, affect many processes controlled by the brain.  These areas include parts of the brain that affect temperature control, appetite, energy regulation, mood, and cognition.

Most women will begin experiencing hot flashes and/or night sweats during perimenopause.  These are caused by alterations in the brain’s “thermostat” triggered by low estrogen.  Hot flashes come and go at unpredictable times throughout the perimenopause as the hormone levels fluctuate.  As time goes on, they become more frequent and bothersome and will persist through menopause and beyond.

Sleep disturbance is another common symptom that arises during perimenopause.  Women note trouble both falling asleep and staying asleep.  Sleep problems occur even in the absence of having hot flashes or night sweats.

Mood changes are prominent during perimenopause.  It is very common for women to feel more anxious, irritable, and depressed.  Women who have had prior problems with mood issues are more at risk, such as women who have had postpartum depression, PTSD, or who have had childhood adversity.

Estrogen also plays many roles in cognition, and during perimenopause women frequently encounter changes in their mental functioning.  This commonly shows up as difficulties with memory, concentrating, problem solving, and multi-tasking.  This spectrum of complaints has been described as “brain fog.”

Women who have a history of migraines often find that their headaches are more frequent during the perimenopause.  This is because migraines frequently are triggered by changes in estrogen levels.

Besides the brain, women note other changes in their bodies, particularly toward the end of perimenopause as the estrogen level drops lower and lower.  The tissues in and around the vagina are particularly sensitive to the loss of estrogen.  They become thinner, drier, and less elastic.  This leads to discomfort and an increased risk of developing vaginal and bladder infections.

In late perimenopause women also encounter changes in how their bodies regulate energy balance and how fat is processed.  One’s appetite tends to be stimulated which can lead to weight gain.  In addition, fat preferentially gets deposited around the middle leading to an increase in belly fat.

Are there health consequences of perimenopause?

There is no question that the symptoms of perimenopause greatly affect a woman’s mental health and quality of life.  However, there are other changes that go on in the body that have major health impacts.

It has been shown that a woman’s bone density begins to decline dramatically during perimenopause.  This rapid loss continues for up to seven years after menopause.  Women who lose a lot of bone during this phase will be at a higher risk for osteoporosis and a fracture in later life.

Estrogen is instrumental in preventing the accumulation of belly fat.  This type of fat can alter the way the body processes sugar and this can lead to an increased risk of diabetes.  In addition, higher amounts of abdominal fat promote inflammatory chemicals and other changes that increase the risk of heart disease.

Other changes occur during perimenopause that affect the cardiovascular system.  The cholesterol level rises and this is primarily due to an increase in the LDL, or “bad” cholesterol.  In addition, studies have shown that women’s arteries become less elastic as they go through perimenopause.  This increases a risk of hypertension and hardening of the arteries.

All of these metabolic and physical changes described above, which are set into play at the time of perimenopause, increase the risk of common medical conditions seen in older age.

Are there specific treatments for perimenopause?

There is no “one size fits all” approach to managing perimenopause.  Treatment depends on the type and magnitude of symptoms that a woman is experiencing.  Infrequent or missed menstrual periods may not require any treatment, but women who are having extremely erratic or heavy periods may opt for taking a low-dose birth control pill.  These will regulate the menstrual cycle, provide birth control if needed, and also treat hot flashes.  (It should be noted that women can get pregnant during perimenopause and are advised to use some form of birth control until they are in postmenopause.)

The most effective treatment for hot flashes is estrogen supplementation.  Women not requiring birth control can be treated with the same hormones used for postmenopausal hormone replacement therapy (HRT), although this requires careful adjustment to avoid aggravating any menstrual irregularities.  Sometimes low-dose estrogen is given only when estrogen levels are at their lowest, such as during the menstrual flow.  Selective serotonin receptor inhibitor (SSRI) drugs, generally used for depression, have been approved to treat hot flashes and some women find these beneficial.  Supplements such as black cohosh may be helpful and some women have found acupuncture beneficial.

Women experiencing primarily vaginal symptoms are encouraged to use vaginal moisturizers and lubricants.  Low-dose estrogen preparations designed only for vaginal use are also very effective and the benefit of using them is that the estrogen therapy will restore the tissue to its previous more “youthful” condition.  These products are extremely safe because very little estrogen enters into the blood stream when these are applied.

Women should be sure to take adequate calcium, vitamin D, and exercise to help prevent bone loss.  Women at high risk for thin bones may be offered a bone density test and may be candidates for further treatment.  At this time, estrogen is not approved if women are desirous of simply taking estrogen to help prevent the inevitable bone loss that will occur in perimenopause and early postmenopause.

Women with depression and anxiety should discuss their symptoms with their healthcare team and may be candidates for mental health counseling.  Anti-depressant drugs can be very helpful and may decrease hot flashes.  Estrogen therapy has been shown to help mood disorders in many studies, but is not approved by the FDA specifically to treat anxiety or depression due to perimenopause.

Women should see their healthcare providers regularly during the perimenopause transition and have their blood pressure, cholesterol, and blood sugar levels monitored.  If elevations are found it is advisable to consider appropriate treatment including lifestyle changes and medications if needed.

As noted, a number of other changes related to estrogen deficiency occur during perimenopause such as the effects on cognition, blood vessels, and fat metabolism.  Instituting estrogen replacement as a means to prevent these problems is not currently approved because there have not yet been sufficient long-term studies to “prove” they will help.  However, women who use estrogen to treat their other symptoms, such as hot flashes, will likely enjoy some benefit in these other areas.

I talk more about perimenopause and discuss why hormone therapy can make a major positive impact on a woman’s life in my YouTube webinar: