My Mum had four children and only had pethidine for the labour for her first child. She swore never again. My sister had pethidine for one of her labours and her way of describing it was "like being locked inside your body whilst you go through hell and not being able to tell anyone about it." On that basis, (and on the basis that it crosses the placenta) I decided against it. I used only the gas during my labour, but if push came to shove I would have taken an epidural over pethidine, any day.

Next time, I hope to avoid the gas. For me, it didn't take away the pain, it only helped me focus on something (breathing in the gas) other than the pain. Towards the end it made me lose focus and I wasn't able to think clearly (although that might have been the cascading contractions )