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Contractions – what causes them?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Well-Known Member
Jan 14, 2003
I’m sorry if this is a silly question. Are contractions triggered by high levels of CO2 (i.e. part of the ‘need to breathe’ mechanism). Or are they triggered by low levels of O2 (hypoxia)?
CO2 - in the fluid around the spine just below your head, I think?

Eric F found a good URL on this subject. Can't remeber where. He may be able to find it again.
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Not long ago I think Eric said although most believe that it is due to high co2 it was actually due to low 02.

You can get contractions from low O2, with hypocapnic levels of CO2.

It seems that contractions can be caused by either CO2 or O2.

Eric Fattah
BC, Canada

Eric what is Hypocapnic, I guess extremely high levels of Co2.


Right I was just a bit off :D Whatever the situation I hate contractions.


so basicly nobody knows exatly what causes contractions.
so there are many factors that can trigger it?

if contractions can be caused either by O2 or CO2 in what case it is triggered by O2 and in what case by CO2?
i would really like to know more about this.


The only thing i know about contractions is that hyperventilation delays them big time, and yep I suck at holding them.

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