Towards the end of your pregnancy you will notice that your bump is sometimes very hard. The uterus is a muscle. At the end of pregnancy that muscle is completely stretched. That muscle responds to any stimulus, such as lifting heavy shopping bags out of the car, a full bladder, running after your toddler. A muscle that is stimulated pulls together. That is a tightened belly, not labor. The fibers of the uterine muscle are not working together.
During a contraction your uterus pulls together too, but in a different way. The muscle fibers work together then. Contractions move in a wave-like motion from the top of the uterus to the bottom. Some women describe contractions as strong menstrual cramp. It comes, rises to a peak and ebbs away again. During a contraction your baby is pushed deeper into your pelvis, the head presses the cervix, causing dilatation.
We call the contractions effective when dilatation progresses with 1 cm per hour or more. This can only be checked with a vaginal examination.
Good contractions are effective contractions, no matter how painful, how long, how hard you need to work coping. The only good contractions of labor are those that lead to adequate progress. Nothing is more frustrating than painful contractions for nothing. You are breathing like you were taught, your partner is rubbing your back, and then we see that dilatation is not progressing. Cooperation between the muscle fibers is not good. This happens especially in women who give birth for the first time.
When dilatation does not progress, even if you are still under3-4 cm, interventions are advised.