Introduction

Women in midlife increasingly hear the words "estrogen deficiency" spoken as the ultimate in bad news. "Everyone knows" that low estrogen levels cause heart disease, osteoporosis, Alzheimer's and frigidity. Right? But as Dr. Susan Love (renowned breast surgeon and author of Dr. Susan Love's Hormone Book) states, "If estrogen deficiency's a disease, all men have it!" [Love 1997]

Our purpose here first is to put women's midlife experiences and concerns into a new and more accurate hormonal picture. Specifically, I'd like to present new information about high estrogen levels in the perimenopause. Not low, not even normal, but estrogen levels that are higher than those of the (sexiest) 20 year-old woman! Secondly, I'll discuss how you can tell when your estrogen levels are high and out of balance with progesterone, the other important hormone for women. And finally, we'll review the many ways a woman can help herself through perimenopause, "Estrogen's storm season!"

What is perimenopause?

Women have often called "menopause" everything they experience during the changing times of midlife. However, now that we know about perimenopause, a hormonally distinct time in midlife, it is important to use the right names. Menopause means that a year has passed since a woman's final period. Perimenopause refers to the long and changing time until a woman "graduates" into menopause. The newest name for perimenopause is "menopausal transition".

The first perimenopausal change commonly masquerades as increased premenstrual symptoms (sometimes called PMS). A regularly menstruating woman may have her first migraine, start waking after two or three hours of sleep and toss and turn. Finally she may suddenly flood during what was a normal period or start having night sweats. On average the perimenopause lasts at least four and commonly eight to 10 years. The good news is that perimenopause ends! I am an expert on the perimenopause primarily because I have now graduated! I survived a rough 10-yr perimenopause and my own experiences told me that the experts had it all wrong about dropping or deficient estrogen levels!

High and swinging, not dropping estrogen levels in perimenopause!

Many studies in the last 20 years have measured estrogen levels in perimenopausal compared with premenopausal women. Each study, however reports by summarizing that estrogen levels are dropping.

Surprisingly, they don't bother to mention the high levels they also found [Burger, Dudley, et al. 1995].

When all of the studies are put together (Figure 1, above), and the average perimenopausal estrogen levels are compared with average levels in young women, it is clear that estrogen levels are about 30% higher than normal during perimenopause [Prior 1998].

Let's consider estrogen levels from a population-based study of over 300 Australian perimenopausal women (Burger, Dudley, et al. 1995). Each woman had a blood test 3-8 days after the start of flow-each woman's level is a dot in Figure 2.

This shows lots of estrogen variation and high levels occurring not only in the regularly menstruating women (group 1) but also in women who were between 3 and 11 months since their last period.

Not only are most of the levels higher than the average end-of-flow estrogen levels for 20-35 year olds (dotted line) but many are even higher than the highest point at the middle of the cycle for 20-35 year olds (solid line). But what did these very good scientists say in summary? "Perimenopause is characterized by dropping estrogen . . .levels" [Burger, Dudley, et al. 1995].

The study we just discussed [Burger, Dudley, et al. 1995] also measured a strange new hormone called "inhibin". I believe it is because inhibin, the ovary's normal brake-type hormone, begins to slack off in its job of keeping the pituitary's Follicle Stimulating Hormone (FSH) in line, that the perimenopausal ovary goes through its grand finale [Prior 1998]. Lower inhibin levels allow FSH to increase and to stimulate several rather than just one follicle (the nest of estrogen-producing cells surrounding an egg). As a consequence estrogen levels rise and become unpredictable [Prior 1998].

The other big hormonal change of perimenopause is that progesterone levels are too low [Prior 2001]. Progesterone, the important ovarian counterbalancing hormone to estrogen which is made after an egg is released, is produced in lower levels even when cycles are still regular [Santoro, Rosenberg, et al. 1996]. We know that normal progesterone levels are needed to prevent bone loss in young women [Prior, Vigna, et al. 1990]. We also know that too much estrogen with too little progesterone makes for heavy periods or frequent flow.