Normal uterine contractions begin at

What are the characteristics of normal uterine contractions during labor? In response to this question, relevant personnel stated that during labor, each uterine contraction lasts about 30 seconds, with an interval of 5 to 6 minutes. As the labor progresses, the duration of uterine contractions increases, the intermittent time decreases, and the strength of uterine contractions also gradually increases. Pregnant women subjectively feel that their uterus is contracting more and more tightly. What are the characteristics of normal uterine contractions during labor?

Uterine contractions during labor are not regular at first, usually once every 30 minutes or once every 10 minutes, then gradually become regular, with the following characteristics:

Regularity

During labor, each uterine contraction lasts about 30 seconds, with an interval of 5 to 6 minutes. As the labor progresses, the duration of uterine contractions increases, the intermittent time decreases, and the strength of uterine contractions also gradually increases. Eventually, uterine contractions lasted for 1 minute, and the intermittent time was reduced to 1 to 2 minutes.

symmetry

During labor, uterine contractions start from the uterine horns on both sides, concentrate in the center of the uterine fundus, and then spread downward and outward. The contraction force is strongest and longest at the bottom of the uterus, and gradually weakens downwards.

Shrinkage effect

After each contraction, the uterine muscles cannot return to their original length. This contraction effect makes the volume of the uterine cavity smaller and smaller, and the lower segment of the uterus is in a passive expansion, which causes the fetus to gradually descend.

In short, uterine contractions tend to be regular and harmonious during labor, which can promote the full dilation of the cervix and force the fetus to leave the uterus. Pregnant women subjectively feel that their uterus is contracting more and more tightly. The abdominal pain moves from the fundus of the uterus to the lower abdomen, and the back pain also worsens. This situation is different from the previous one, and pregnant women can clearly see that they are about to give birth. As the uterus enlarges, the capacity of the uterus gradually decreases, causing the presenting part to continue to lower until the baby is delivered.

Disharmony and weak uterine contractions

The optical rotation of uterine contraction is reversed. The contraction does not start and spread symmetrically from the uterine angle, but the climax points may be located in one or several places in an irregular pattern. The uterine contraction is weak in the terminal fundus while strong in the middle and lower areas. The uterus does not completely relax when the uterus contracts intermittently. This will not allow the cervix to expand and the presenting part to drop, resulting in dystocia and fetal distress, once surgery is performed. The chance of trauma also increases, and pregnant women may suffer compressive necrosis of some tissues (uterus, bladder, urethra) due to delayed labor.