From: sfm@manduca.neurobio.arizona.edu (Stephen Matheson)
Newsgroups: talk.abortion
Subject: Re: Peter shows his ignorance, once again.
Date: 24 Dec 92 15:52:51 GMT
Organization: University of Arizona UNIX Users Group

From article <nyikos.725147807@milo.math.scarolina.edu>,
by nyikos@math.scarolina.edu (Peter Nyikos):

> In <1992Dec22.010745.13877@mnemosyne.cs.du.edu>
> mcochran@nyx.cs.du.edu (Mark A. Cochran) writes:

>>In article <nyikos.724963465@milo.math.scarolina.edu> nyikos@math.scarolina.edu (Peter Nyikos) writes:

[Lots deleted]

This is Loren writing:

>>>>>Except the fertalized egg will grow into an embryo...adult.  There
>>>>>is a difference between growing into something (fertalized egg ->
>>>>>Embryo), and being changed into something by outside forces
>>>>>(unfertalized egg -> fertalized egg)

[Commentary on ability to spell and state of American education omitted
reluctantly.]

[Deletions]

Mark Cochran is writing here (I think >:-|)

>>>>You statement above, in order to be correct, should read:
>>>>"Except the fertalized egg [your spelling. I'll be happy if you get
>>>>the biology correct. Somebody else can undertake to teach you to
>>>>spell] may, under circumstances which occur for perhaps one out of
>>>>three fertilized [correct spelling, since it's my word this time...]
>>>>egg, implant,

>>>Source, please, for the "one out of three" statistic.

>>Any text on obstetrics. Pick one, any one, and read it.

I was curious about this, so I checked my embryology text.  Here's
all I could find:

 About 15 per cent of all zygotes result in detectable spontaneous
 abortion, but this estimate is undoubtedly low because the loss of
 zygotes during the first week is thought to be high.  The actual 
 rate is unknown because the women do not know they are pregnant at
 this early stage.

 It has been estimated that from one third to one half of all zygotes
 never survive to form blastocysts and implant.  Failure to implant
 may result from a poorly developed endometrium, but probably in many
 cases there are chromosomal abnormalities in the zygote.

From:  Keith L. Moore (1983) _Before We Are Born: Basic Embryology and
Birth Defects, 2nd ed._  pp. 28, 38

I could find no evidence for high rates of spontaneous abortion *after*
implantation.  I suspect that there is no such evidence.  Cochran's
claim that perhaps one third of all zygotes implant is a little
exaggerated but still in the right (major league) ballpark.

[Much more deleted.  You're welcome.]

>>>> and begin the process by which it may (again, against
>>>>the odds) eventually become an embryo, a fetus,
>>>
>>>Source, please, for "against the odds".  I've seen this kind of talk
>>>bandied about for months in talk.abortion, all without a scrap of
>>>documentation.
>>>
>>Any text on obstetrics. Pick one, any one, and read it.
> 
> Gee, how many pages do I have to read to get the exact statistics, which
> you haven't even given us a clue on?  C'm' on Mark, what are the odds
> against the implanted BLASTOCYST -- or is it a MORULA, Mark?  I know
> it's not a FERTILIZED EGG, or are you THIS  willing to contradict
> Larry Margolis?? -- eventually becoming (1) an embryo, and (2) a fetus?

I have documented above that the odds against implantation are pretty
long.  I can find no odds for or against the implanted blastocyst
developing further into an embryo or a fetus.  Are you sure this is
what Cochran was referring to?  If so, I join you in requesting more
information, which I suspect does not exist.

--

Steve Matheson   Program in Neuroscience   University of Arizona
sfm@neurobio.arizona.edu
Newsgroups: talk.abortion,talk.religion.misc,alt.atheism