What is menopause (and the other phases before and after)?

Technically, the term menopause refers to the point in time when a woman is no longer fertile and when the last viable egg has been released. It’s pretty amazing that we’re born with over 3 million eggs nestled in our ovaries and by the time we reach menopause they have all disappeared.  You only release one egg a month over your reproductive life span – so if you do the math that comes out to be around 500 ovulations.  The rest of those millions of eggs mysteriously disappear through a preprogrammed auto-destruct process that nature has built into our system.

You can never be sure when that last egg will be released to know if you can officially say that you have reached menopause, but it usually is around the age of 50 (plus or minus 5 years).  For several years before the time of the final menstrual period, a woman may skip an ovulation or two and therefore will have irregular periods.  So, she never knows when she will finally quit.  So, by convention, we consider that a woman has reached menopause if she goes for 12 months without a menstrual period.  Prior to that time she is considered to be premenopausal. Those years just prior to the menopause are called the perimenopausal years, and this period can last anywhere from two to ten years (more on this phase below).  The final stage is the postmenopause, and so for the many years following menopause, the proper designation is that a woman is postmenopausal.

Besides being the reservoir for our eggs, the ovaries are the main source of estrogen and progesterone.  Women experience changes in their hormone levels as the ovaries evolve during these life phases. During the premenopausal years there is a predictable cyclic rise and fall of our two main female hormones, estrogen and progesterone.  These changes prepare a woman for pregnancy and thus those years are referred to as the reproductive years. The levels of both hormones are very low at the start of each menstrual cycle. Then the estrogen level rises, which is followed by a surge of progesterone mid–cycle.  Both hormones peak and remain elevated for the second half of the cycle then fall quickly back to baseline levels (if a woman does not get pregnant).

As a woman approaches menopause the ovaries wind down in their ability to make hormones. So a woman may experience various levels of either hormone in any given month.  Some months may be normal. During other months the estrogen and progesterone levels may be low, high, or out of sync.  This leads to irregular periods and abnormal bleeding.  The hallmark of the perimenopausal phase is inconsistent bleeding and irregular ovulation.

The perimenopausal period is sometimes the most difficult phase to deal with. Having unexpected spotting or heavy bleeding is frustrating, and missing a period for up to several months in a row can lead to a panic moment wondering if you are pregnant. (Yes, you can get pregnant even with your last egg!) In addition, each month with its unpredictable hormonal levels can bring on an array of unwelcome symptoms. During the times of low estrogen women can experience hot flashes, night sweats and sleep disturbance.  Those cycles characterized by unbalanced estrogen and progesterone bring on breast tenderness, food craving, bloating and mood changes.  Feeling terrible one month and then perfectly normal the next month can make you feel like you’re losing your mind.  It’s no wonder that back in the 1800’s women were sometimes diagnosed with insanity during this phase of their lives! *

When we finally reach menopause the ovaries have essentially quit producing hormones. There are low levels of estrogen and progesterone that come from other sources, but they are a fraction of their prior levels.  When the ovaries shut down naturally between the ages of 45 and 55, we call this natural menopause.  A number of factors can influence this – family history and ethnic background being major ones.  Women who smoke or are malnourished tend to go through menopause earlier as do women who have had a hysterectomy.

If a woman has to have her ovaries removed by surgery, we call this surgical menopause. Usually these women have a much stormier course because of the sudden and abrupt loss of not only estrogen and progesterone but also testosterone (which is also made by the ovaries).  There are also a few other things that can cause irreversible ovarian damage such as an infection or an auto-immune process that can push a woman into menopause.

Other than being without a period for 12 months, there is no surefire way of diagnosing menopause. There are blood tests, but since they can fluctuate month to month, they need to be interpreted with caution.  However, if serial readings show a pattern of ovarian decline, they can be fairly good indicators of where a woman is in her transition into and through menopause.  Typically the estrogen levels gradually drop, and a test called the FSH (follicle stimulating hormone) starts climbing.  A relatively new test, called the AMH (anti-mullerian hormone) also appears to correlate with the number of eggs remaining in the ovaries and is being used to predict how many more fertile years a woman has left.

In future blogs, I will be discussing much more about the effects of estrogen, progesterone and testosterone in our bodies and how the loss of all of our hormones affects us when we go through menopause.

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*I can’t resist inserting this quote from 1887:

“The ovaries, after long years of service, have not the ability of retiring in graceful old age, but become irritated, transmit their irritation to the abdominal ganglia, which in turn transmit the irritation to the brain, producing disturbances in the cerebral tissue exhibiting themselves in extreme nervousness or in an outbreak of actual insanity.”

From: Farnham AM. Uterine Disease as a Factor in the Production of Insanity. Alienist Neurologist 1887: 8:532