Cervix progression to birth

cervical dilatation

Active labour! This usually begins when a womans cervix is 4cm dilated AND she is having strong regular contractions every few minutes. Once you are at this point, there is no turning back! A baby will arrive soon.
Every woman is different and the speed at which your cervix dilates depends on lots of factors including:
-whether its your first baby or not. If it's your first, your cervix has never dilated like this before so will usually take a bit longer than someone who has already gone through it.
- The position of the baby. A baby who is 'back to back' is likely to cause labour to be longer as there isn't in the optimal position to put the correct pressure on the cervix and help it to efface and dilate.
- If the head is high. If the head is not low enough, it might take longer for it to dilate, again due to limited pressure from the head on the cervix. 
Things you can do to promote a quicker labour:
Keep as mobile and upright as possible, remain hydrated throughout and ensure you are in a birth environment you feel comfortable whether that be home, birthing centre or hospital.