Once labour starts, there are many factors that have the potential to influence the woman's perceived intensity of her pain. Labouring women are very sensitive to their environment, the people around them, as well as being faced with unexpected complications, or a labour for which they were not mentally prepared for.
Some factors that can influence a woman's individual perception of her labour pain can include:
The type of labour the woman is having
Exhaustion
Complications arising
Pain relief not meeting expectations
The caregivers influence.
The support persons influence
The type of labour the woman is having. Many women approach their labour with unconscious time frames on how long it will last. Unmet expectations can lead to less tolerance of the pain and possibly more acceptance of medical pain relief, as she tenses and 'fights' the labour she is experiencing, rather than accepting that 'this is how it is'. Sometimes 'time limits' can come from the caregiver and in some cases be unreasonable, especially when the mother and baby are still physically well. The suggestion of intervention 'in an hour' if no progress has been made, places pressure on the woman to 'perform', even though she was probably feeling 'OK' before time was made an issue. You may wish to read
slow progress in labourin Class 4.
Exhaustion and tiredness during labour is usually a normal sign of the natural endorphin release by the woman in labour. True exhaustion is possible, but not that common in reality. If the woman is truly exhausted (and not just in the transitional phase of labour), then she can become irritable and feel less able to cope with her labour pain. The pain can feel more intense and be less tolerated, especially if the prelabour or labour is prolonged. Dehydration can compound this, causing the woman to feel weak and lethargic, as well as possibly slowing her labour down. You may wish to read
dehydration and ketosisfor tips on avoiding dehydration.