The NY Times
June 6, 2004

By SUSAN LOVE, M.D.

We have just undergone a seismic shift in our understanding
of the second half of women’s lives and the aftershocks
will continue for some time. So if you’re confused – it
means you’ve been listening.

These big changes come in medicine when new data show that
we were on the wrong path. It can be upsetting to everyone
who thought they had the answer, but it can also be
refreshing. New information forces us to re-evaluate our
preconceived notions no matter how we came to them.

For example, I was taught in medical school that at
menopause the ovaries stop functioning, shrivel and dry up.
(In fact, I was taught that that was what happened to
postmenopausal women as well.)

The problem was that we did not have tests sensitive enough
to detect low levels of hormones in the blood, so we
thought postmenopausal women did not produce any of these
hormones. Studies treated women who had undergone natural
menopause and those who had had their ovaries removed as if
they were the same.

Now we know that the ovaries do not stop producing
hormones; they just shift to a much lower level, a level
that is probably enough to prevent fractures and maintain
libido in most women.

With that knowledge, we need to go back and carefully study
which menopausal and postmenopausal problems are related to
the surgical removal of ovaries and which are tied to the
natural course of menopause itself. And we still need to
develop blood tests that can more reliably measure a
woman’s hormone levels. That’s the only way we will know
what is normal for a postmenopausal woman.

Since the conclusions in 2002 of the Women’s Health
Initiative, which studied the effects of hormone
replacement therapy using the popular formulations Premarin
and Provera, several studies have examined the effects of
other variations of estrogen and progestin that are more
like the hormones a premenopausal woman would make
naturally.

For example, the Million Women Study, a British study
reported in 2003, showed that even estradiol and
progesterone, which have been considered bioidentical
hormones, increased the incidence of breast cancer; and
Well-Hart, a national study reported in 2003, showed that
estradiol did not prevent the progression of
atherosclerosis. These findings are supported by the fact
that postmenopausal women with high levels of their own
natural estrogen and/or testosterone are at higher risk of
breast cancer than women with lower levels.

THE problem with hormone therapy does not lie in the
“flavor” of hormones (bioidentical or synthetic), but the
fact that women are programmed to have high levels of
hormones for reproduction and then shift down to lower,
safer levels postmenopausally. However, even this, my
favorite hypothesis, needs to be tested.

We can no longer take for granted that we understand how
postmenopausal women’s bodies work. We need to pay more
attention to individual organs. The breast duct and
lobules, where breast cancer begins, contain fluid with
estrogen levels many times higher than the levels in the
blood. This would suggest that the breast makes its own
estrogen. Is this true in everyone, or only in women with a
high risk for breast cancer?

And the relationship of estrogen and progesterone to breast
cancer is not straightforward. High doses of estrogen and
progestin have been used to treat metastatic breast cancer
with success. At the same time, current treatments, which
reduce estrogen levels, are equally beneficial. How does
this work? I wish I knew.

The one thing we know for sure is that it’s time to get the
elephant out of the middle of the room. Until these recent
studies overturned the theory, we have blamed all the
diseases of aging, from Alzheimer’s to incontinence, on
“estrogen deficiency.”