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It seems that one of the possible obstacles facing a woman who
wants to become pregnant is her own immune system --it can
attack normally-deposited sperm to the extent of preventing
them
from reaching an ovum. In the same place where I encountered
that fact, I also encountered a suggestion
to the effect that in-
vitro fertilization was a possible solution. That particular
process
involves removing a ripe ovum (quite invasive), external
fertilization of it, and the additional invasive-ness of
attempting
to get the result to implant into the uterus. The success rate is
somewhat low, and the price of the procedure is rather high.
Well, I think I have a much simpler and less expensive solution.
Both solutions require a container of semen to be collected
(cheap
and easy). Normal artificial insemination would deposit the
semen in the same place that normal natural insemination would
deposit it. With respect to the problem described at the start
of
this text, artificial insemination would be no better than the
natural type, simply because in either case the sperm has to run
an immune-system-defended path to reach the ovum.
Logically, if a tube can be extended from the outside, into the
Fallopian Tube to extract a ripe ovum, that tube could instead
be
used to deliver sperm to that location. Most of the defended
path
thus gets bypassed, the chance of fertilization then becomes
about as good as if it was done in a Petri dish, and no second
invasion need be done, to get the result to implant into the
uterus
--that normally happens naturally.
[link]
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I'm aware it may be necessary to extract sperm from semen
for this Idea to work properly, as described (we don't want
the semen to clog the Fallopian Tube to the extent that a
fertilized ovum can't reach the uterus). So? Even with that
extra step this should still be less expensive than the in-
vitro method. |
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Uh, [vernon], you do realize that when they collect eggs for IVF,
they don't just stick a hose up the fallopian tube until they hear it
hit an eggshell? |
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Human oocytes are collected by aspirating them directly from the
follicles in the ovary. And you probably don't want to go putting
sperm in there. |
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[MaxwellBuchanan], fertilization normally takes place
inside a Fallopian Tube near the ovary (but not inside
the ovary). I'm talking about naturally ripened ova,
and I know that women can use temperature
measurements to determine when ovulation happens. I
admit to assuming that knowledge of that event is then
used to begin an ovum-collection effort. What you
describe seems more about gathering not-quite-ripe
eggs? Which would then be ripened artificially? |
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Anyway, there are cilia inside the Fallopian Tube to
transport a fertilized ovum to the uterus. ETA is three
or four days, the same time it takes the zygote to divide
several times and become ready to break out of the
"eggshell" associated with the ovum ("zona pallucida").
The biological entity that emerges is called a
"blastocyst", and it implants into the uterus. If the
Fallopian Tube has damage or a blockage that prevents
the fertilized egg from reaching the uterus, the
blastocyst would emerge inside the tube and might
implant into the tube, causing a dangerous "ectopic"
pregnancy. |
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Regardless of whether a ripe ovum is fertilized, it is
transported by the cilia toward the uterus. It could get
fertilized about the same time it reaches the uterus,
but three or four days are still needed before a
blastocyst can emerge, and during that time the
organism could literally fall out of the womb and be
lost. I am NOT working against Nature in suggesting
artificially delivering sperm up-close to the point of
ovulation, simply because that is the normal
fertilization location. |
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What I wrote in my previous anno was about the
awareness of the fact that semen has physical
properties that could let it cause a blockage for a
fertilized egg, if semen was directly introduced into the
Fallopian Tube. Separating sperm from semen would
be a Good Thing. |
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Maybe it would be better to grow kids the same way they did in Space Above and Beyond. |
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Well, there is a thing called intrauterine
insemination, which is sort of going in that direction. |
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Incidentally, the commonest cause of infertility in older women is that the
majority of oocytes are aneuploid (having missing or extra chromosomes),
and produce embryos that are either completely unviable, or only make it
through a few cell divisions. IVF helps, somewhat, because large numbers
of oocytes can be collected and fertilized, and several embryos can be
implanted in the hopes of getting one good one. There are many
technologies which aim to identify the euploid oocytes, but it's still
difficult (I know, because I have an ongoing collaboration with a German
IVF research centre on this very topic). |
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So, is it a turkey baster? |
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//So, is it a turkey baster?// |
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Happy Thanksgiving, everyone! Hope you have that visual in
your head when chowing down on stuffed bird this
evening! |
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