I think every birth experience is different and every woman has a different way of coping. I certainly don't think a woman can be accused of being hysterical or over the top if she screams during labour. Without drugs it has to be the most intense pain a woman will ever experience in her life. I did a hypno-birthing course and did all the relaxation and breathing techniques but it was impossible for me to stay calm at the very end of my labour and I feel totally conned to have been told the whole thing could be pain free - it has to be the biggest lie out there!
I coped ok-ish with the contractions i.e. I didn't scream, just groaned loudly. However, when it came to pushing my 9lb plus baby out, who got stuck and needed to be delivered by ventouse, after an episiotomy (all on gas and air), I screamed the place down - the pain was agonising. I never want to experience that again and will be demanding my epidural next time!