Barbara Ehrenreich has authored a long list of books on a
variety of topics. Perhaps her
best-known work is Nickel and Dimed: On (Not) Getting By in America. She has occasionally chosen topics that
involve healthcare, but the focus was not such as to allow one to suspect that her
formal education resulted in a doctorate in cellular immunology from
Rockefeller University. Apparently,
her range of interests were too broad to be constrained by a career in such a
narrow discipline. It would be awareness
of a growing revolution in knowledge of how the human immune system actually
worked that would lead her back to her original field for the production of her
recent effort: Natural Causes: An Epidemic of Wellness, the Certainty of Dying, and Killing Ourselves to Live Longer.
As the title suggests, Ehrenreich is dubious about the prospects of
extending life indefinitely, and she is not at all optimistic about our
prospects for making significant changes in our longevity by changing our
personal lifestyles.
“The body….is not a
smooth-running machine in which each part obediently performs its tasks for the
benefit of the common good. It is at
best a confederation of parts—cells, tissues, even thought patterns—that may
seek to advance their own agendas, whether or not they are destructive of the
whole. What, after all, is cancer, other
than a cellular rebellion against the entire organism.”
“I know that in an era where
both conventional medicine and the wooliest ‘alternatives’ hold out the goal of
self-mastery, or at least the promise that we can prolong our lives and improve
our health by carefully monitoring our lifestyles, many people will find this
perspective disappointing, even defeatist.
What is the point of minutely calibrating one’s diet and time spent on
the treadmill when you could be vanquished entirely by a few rogue cells within
your own body?”
It was recent knowledge gained about the role of our
immune systems in determining our health that prompted her to write the book. To perform its function of protecting us from
things like microbes and parasites that are foreign to our bodies, the immune
system consists of an impressive array of structures and processes designed to
disable or destroy these things. However,
the power to destroy can be dangerous if malfunctions can occur. And they do.
There are at least 80 types of autoimmune diseases where the
immune system, for whatever reason, turns on specific body parts. Examples include rheumatoid arthritis, lupus,
celiac disease and Graves’ disease. Her
coverage of issues related to the immune system was discussed in Cellular Conflicts: Is Extending Life Possible—or Even Worth the Trouble?
The topic here involves another instance of cellular
conflict within our bodies: the human female reproductive cycle. It has been recognized for over twenty years
that pregnancy involved a competition between the host mother and the fetus she
was carrying.
“In 1993….[David] Haig put forth
the surprising view that pregnancy was shaped by ‘maternal-fetal competition.’ The fetus and the placenta that attaches it
to the maternal bloodstream strive to extract more nutrients from the mother,
while maternal tissue fights to hold on to its nutrients—often to the detriment
of the mother. For example, the fetus
may interfere with maternal insulin production, leading to elevated blood sugar
levels that are injurious to the mother but deliciously nourishing to the
fetus. Or the fetus and the placenta may
release chemicals that raise the mother’s blood pressure—apparently to guarantee
a steady flow of nutrients to the fetus—although at some risk to the mother and
ultimately to the fetus as well.”
What is less well known is that cellular conflict begins
much earlier in the process. In
preparation for encountering a recently created embryo, the uterus generates a
relatively thick layer of cells referred to as the endometrium. It was thought that this layer was produced
in order to provide an efficient harbor in which an embryo can dock and set up
shop. However, it seems that a woman’s
uterus is very particular about which embryos it is willing to allow to attach to
it. The role of the endometrium is, counterintuitively,
to make it difficult for an embryo to attach and access the mother’s blood
stream.
“Today the emerging scientific
consensus about menstruation hinges on the conflict within our species—a possibility that would until recently have
been deeply disturbing to biologists. In
this view, the buildup of the uterine lining does not serve to entice embryos
to implant, but to prevent all but the most robust and agile embryos from ever
having a chance.”
To support this view, Ehrenreich references an article by
the evolutionary biologist Suzanne Sadedin: Why do women have periods? What is the evolutionary benefit or purpose of having periods? Why can’t women just get pregnant without the menstrual cycle? From it, this quote was extracted.
“Far from offering a nurturing embrace, the
endometrium is a lethal testing-ground which only the toughest embryos survive.
The longer the female can delay that placenta reaching her bloodstream, the
longer she has to decide if she wants to dispose of this embryo without
significant cost. The embryo, in contrast, wants to implant its placenta as
quickly as possible, both to obtain access to its mother's rich blood, and to
increase her stake in its survival. For this reason, the endometrium got
thicker and tougher – and the fetal placenta got correspondingly more
aggressive.”
Sadedin included a reference to a more detailed
scientific paper that provides even greater enlightenment: Natural Selection of Human Embryos: Decidualizing Endometrial Stromal Cells Serve as Sensors of Embryo Quality upon Implantation. This paper was authored by 18 individuals
with mostly unpronounceable and, certainly, untypable names. A critical insight provided by these authors
is that a significant fraction of human embryos are defective at a chromosomal
level.
“Monthly fecundity rates in
fertile couples average around 20%, which is disappointingly low compared to
many species. While this lack of
intrinsic reproductive efficacy may reflect a multitude of complex social and
biological factors, for example the loss of estrous behaviour and concealed
ovulation, it is foremost attributable to the high prevalence of chromosomal
abnormalities in human embryos, which limits their developmental potential and
accounts for the age-dependent decline in fertility.”
Unless humans evolved some mechanism for dealing with
this, a woman’s pregnancy would often be unproductive, wasteful in terms of
maternal resources, and dangerous for the woman. Consequently, endometrial cells, driven by
hormonal surges produced during the menstrual cycle, undergo a transformation referred
to as decidualization. It is these
decidualized cells that query the integrity of the embryo and attempt to
destroy those deemed unacceptable.
“Pregnancy is widely viewed as
dependent upon an intimate dialogue, mediated by locally secreted factors
between a developmentally competent embryo and a receptive endometrium.
Reproductive success in humans is however limited, largely because of the high
prevalence of chromosomally abnormal preimplantation embryos. Moreover, the
transient period of endometrial receptivity in humans uniquely coincides with
differentiation of endometrial stromal cells (ESCs) into highly specialized
decidual cells, which in the absence of pregnancy invariably triggers
menstruation.”
“….rather than being passively
invaded, these observations suggest that decidualizing ESCs actively
encapsulate the early human conceptus. If so, the phenomenal response of
decidual cells to a developmentally impaired embryo could represent a mechanism
for controlled embryo disposal, mediated by induction of menstruation-like
tissue breakdown and shedding.”
“….once the endometrium
undergoes a decidual response, the integrity of the tissue becomes inextricably
dependent upon continuous progesterone signalling. In the absence of pregnancy,
declining progesterone levels triggers a switch in the secretory repertoire of
decidual stromal cells….which activates a sequence of events leading to tissue
breakdown and menstrual shedding.”
So, there you have a concise description of the process
of uterine attachment by an embryo. The
endometrial layer captures and “encapsulates” as many of the defective embryos
as it can and destroys them by flooding them with menstrual blood filled with cells
capable of consuming the decidual layer and flushing the debris away. Within the debris are the remnants of what
were once embryos.
What we are encountering here is a process akin to contraception
or abortion. This evolutionarily
developed process decides which embryos are desirable and destroys the
rest. Nature has devised a scheme by
which abnormal or otherwise unwanted embryos can be forbidden to make a
permanent attachment to the uterus and continue into pregnancy. Contraception and abortion, by this
rendering, are not “unnatural” processes as often claimed. They are, in fact, perfectly natural—and
critical to the health of our species.
It would seem that nature is pro-choice, and, if one
wishes to believe that humans were designed by God, then God is pro-choice as
well. People who would determine during
pregnancy that a fetus is damaged in some way have the technology to safely terminate
that pregnancy. In doing this, it would
seem that they are assisting in the plan laid out by nature—and God. Those who would legislate rules that require
a woman to carry a damaged fetus to term are certainly following an unnatural—and
un-Godly—path.
The interested reader might find the following articles
informative:
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