Estrogen alone is
associated with an
increased risk of breast cancer.
Now it appears that progestin may increase the risk
of breast cancer even more than estrogen alone.
The longer a woman takes HRT, the greater her risk.
The standard retort to concerns about breast
cancer has been: but estrogen does reduce the risk of osteoporosis
That remains unchallenged: estrogen decreases
the amount of bone that is reabsorbed in the
constant process of skeletal building and
demolishing.
But estrogen's killer app is supposed to be preventing heart disease.
It is supposed to lower bad LDL cholesterol and raise good
HDL.
That heart benefit
was supposed to swamp the risk of
breast cancer, especially since heart disease kills
nine times so many more women every year
than does breast cancer.
But results of the newest,
best-designed studies find that
HRT provides no heart benefits to women
with existing cardiovascular disease; it may
actually increase their risk of heart attacks.
And it may
not protect healthy women from
developing heart disease: in April, researchers at
the Women's Health Initiative, run by the
National Institutes of Health, warned that HRT
seems to raise the risk of heart attacks and
stroke in healthy women, at least initially.
The Undiscovered
Science of the ORGASM
Why, from an evolutionary point of
view, do women have orgasms?
Unlike the
male ejaculation, the women's climax does not appear to be necessary for
reproduction. The traditional answer,
put forward by Don Symons, the anthropologist in 1979, is that female
orgasm is a relic of Darwinian
sloppiness, like male nipples.
Lately some anthropologists
have speculated that the sweet aftermath of ecstasy paroxysm kept women
passive, facilitating insemination.
The problem there is that Nature did not design
most women to climax reliably through intercourse,
especially not in the missionary position.
The evolutionary biologist Sarah Blaffer
Hardy proposed that women in an earlier age, by sleeping around could
tap these partners for resources, and count on their confusion about
paternity for further
generosity.
Or maybe a satisfying orgasm allows women to influence which mate
will father their
children.
At the University of New Mexico, Randy Thornhill and Steven Gangestad
found that,
other things being equal, women were more
likely to climax when their partners' bodies matched well with theirs.
One way of getting the right genes.
British biologists Robin Baker
and Mark Bellis actually went so far as to attach micro video cameras
to the ends of men's
penises, and found that women retained more
of their partners' ejaculate if they reached orgasm
as well.
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