Why labour hurts 3

Imagine you are a cave woman coming toward the end of your labour when a saber toothed tiger appears at the cave door. OMG. The first thing you would do is to release adrenalin into your system so that you have extra energy to run away or stay and fight. But 'Oh No' your cervix is nearly fully dilated, if your baby is born now then the tiger will think its her birthday and celebrate with a very fresh human, covered in a tasty liquour dressing accompanied by a side order of bloody placenta. Yum.
Mother nature however has other tricks up her sleeve and has put receptor or binding sites on the cervix for adrenalin. The adrenalin secreted when we are under physical or mental stress 'sticks' to the cervix and helps to stop it from opening. Your cave baby is thus held in utero untill you can run out of the back cave door leaving your cave buddies to scare off the tiger. Sorted. Or is it?
Unfortunately mother nature has not moved with the times. Curse you evolution. In the modern world we no longer need adrenalin receptor sites on our cervix and they have become a hindrance. Todays modern woman is so afraid of going into labour that as soon as she does the adrenalin produced from the mental stress will attach itself to the cervix and hinder dilatation. The contractions will have to become stronger in order to heave the resisting cervix up and so become painful.
Howells et al (2000) was a piece of research which compared injecting the uterine cervix before surgery with adrenalin or another substance. The adrenalin worked best at reducing blood loss as it caused the cervix to become rigid. This is similar to how adrenalin performs during labour when levels are high enough to affect the cervix.
A relaxed person does not secrete adrenalin. Relaxation techniques previously discussed in this blog can be used in pregnancy and labour to prevent the cervix being restricted in its dilatation. This should make the labour shorter and easier and end all the cries of " What do you mean I'm not in labour? I've been contracting for 2 f***ing days and my cervix has still not dilated?" Oh bliss.