hmm
my cx felt like BH but BH were up high and these were down low in my stomach
they felt like tightenings- i was lucky they didnt hurt and i just breathed throught them
they are ver similar to BH but just constant.
I also felt my cx in my back rather than my front as well- just felt heavy and tight

i might not be the best to ask as i didnt find my birth painful at all- i know i am a freak lol