From: fulk@cs.rochester.edu (Mark Fulk)
Subject: Re: My wife drank during her pregnancy and the baby lived!
Organization: Computer Science Department University of Rochester
Date: Sun, 11 Oct 1992 04:58:15 GMT

>In article <brein-071092154633@128.149.100.150> brein@gpvax.jpl.nasa.gov (Barry Rein) writes:
>It seems to me that the hysteria about drinking during pregnancy is just
>that, etc.

The recent decision to advise against all drinking in (especially early)
pregnancy dates to about 1985.  At that time, a group of researchers was
studying the effects of alcohol on baboon fetuses, as an approach to fetal
alcohol syndrome.  Early on, they attempted to find an answer to the most
basic and obvious question: how much alcohol crosses the placenta?  To do
so, they dissected out the umbilical cord of an in-utero baboon fetus
(putting the mother under anesthesia, I assume), then administered a
shot of grain alcohol (via naso-gastric tube, if I recall correctly).
They started drawing blood samples from the cord.

The result?  No alcohol!  What's even more amazing, no blood!  The umbilical
cord shut down, becoming visibly empty of blood for some time.  The
experiment has been replicated with the same results.  Evidently, (and not
so surprisingly, in hindsight) the placenta actively _defends_ the fetus
against blood alcohol.  This may seem strange in baboons, other than dorm
apes, but in fact ethyl alcohol does arise in nature fairly commonly.
African elephants sometimes get pretty sloshed from a fermented fruit they
like, for a frightening example.

This leads naturally to the conjecture that fetal alcohol syndrome does not
arise directly from alcohol poisoning, but rather from repeated short periods
of anoxia.

This gave rise to concern because of the following observation: it is known
that in animals, and probably in people, there are a number of tightly timed
and very critical processes in early fetal development.  One good example is
the fusing of the palatal shelves, which, when incomplete because of some
disturbance, leaves a child with a cleft palate and possibly other cranio-
facial anomalies.  Some researchers believe that autism is the result of a
similar interruption in the development of the temporal lobes of the brain.
I would note here that cranio-facial anomalies are common in babies suffering
from fetal alcohol syndrome.

So the suggestion is: perhaps most alcohol consumption in pregnancy is pretty
harmless.  But sometimes, a pregnant woman will have a drink when her fetus
is going through one of these critical stages.  It makes sense that the
resulting anoxia might disrupt the progress of that stage, perhaps leading
to a neural tube defect, a cranio-facial anomaly, retardation, or autism.

Perhaps fetal alcohol syndrome is just the result of many such accidents.
The high degree of variability among the various aspects of FAS certainly
fits well with this explanation.

At the present state of our knowledge, we cannot estimate what the
probability of harm is.  An epidemiological study, at least one that
properly rules out all of the other factors that might be involved, seems
nearly impossible to do.  However, a believable mechanism has been suggested
and has received some empirical support.  From this, some authorities have
concluded that it is best to advise total abstinence from alcohol during
pregnancy, especially in the first trimester.

Now, with all of that said:

Some people seem to have the attitude that a woman who drinks, smokes, uses
other recreational drugs, eats chocolate, drinks coffee, rides a bicycle,
works late, or so forth, simply does not care about her baby.  I have seen
astonishing public displays of contempt for smoking pregnant women.  Given
the enormous difficulty of ceasing the first five habits, I don't believe
that this treatment should be condoned.  People with addictions have a very
hard time.  Pregnant women have a hard time.  Mistreating them doesn't help,
and there is already a large program of public education (at least hereabouts)
on the potential harm to a fetus of drug addiction, smoking, and drinking.
If you want to help a woman's baby, help the woman.

-- 
Mark A. Fulk			University of Rochester
Computer Science Department	fulk@cs.rochester.edu