Prognosis of labor with internal hysterography
Last reviewed: 23.04.2024
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The method of two-channel internal hysterography allows prediction of labor for the whole process of birth. In this case, it is sufficient to record intrauterine pressure in 2 channels within 30-60 minutes from the onset of labor, and then compare the recordings of intrauterine pressure in the region of the bottom and the lower segment of the uterus. By the ratio of the amplitude of uterine contractions predict the course of labor. If the amplitude of uterine contractions is higher in the lower segment than in the bottom of the uterus, the labor proceeds and will proceed normally, but if the amplitude of uterine contractions is higher in the region of the uterine fundus than in the lower segment or is equal to it, there is a weakness in the labor activity.
Thus, with normal delivery, intrauterine pressure in the region of the lower segment when opening the uterine throat 2-4 cm is 43.63 ± 1.01 mm Hg. P. At 5-7 cm - 48.13 + 1.05 mm Hg. P. At 8-10 cm - 56.31 ± 1.01 mm Hg. Art.
In the bottom of the uterus, respectively, 36.6 ± 0.9 mm Hg. Article, 40.7 ± 0.76 mm Hg. St., 47.15 ± 1.4 mm Hg. Art. (p <0.05).
In the practice of the doctor, for the rapid evaluation of the contractile activity of the uterus during labor, the following formula is used:
E = Ea × e / T (conditional e), where
E is the efficiency of the contractile activity of the uterus in conventional units, E is the mathematical sign of the sum, f is the amplitude of the unit reduction in g / cm 2, and T is the time of the process being analyzed in seconds.
The effectiveness of contractile activity of the uterus increases with the progression of labor, while the uterus bottom works more efficiently than the body, and the body - more efficiently than the lower segment of the uterus, although not in all cases, these differences are statistically reliable.
Thus, with a sharply shortened cervix, the efficiency of the contractile activity of the uterus in the bottom area was 13.5 ± 0.43, the body - 13.2 ± 0.45 and the lower segment of the uterus - 7.4 ± 0.18. When the opening of the uterine pharynge is 2-4 cm, respectively, 29.8 ± 0.51; 18.8 ± 0.39 and 13.8 ± 0.28.
When the opening of the uterine pharynx is 5-7 cm, respectively: 30.4 ± 0.63; 19.4 ± 0.48; 14.0 ± 0.31.
When the opening of the uterine pharynx is 8-10 cm, respectively: 36.2 ± 0.59; 24.1 ± 0.32 and 16.8 ± 0.32.
Current research shows that normal amniotic pressure rises as pregnancy progresses and the amount of amniotic fluid increases to 22 weeks, and then does not change significantly. Amniotic pressure and its changes associated with uterine activity are studied for 40 years.
Amniotic pressure during polyhydramnios is high and low - with low water levels. Various complications in pregnancy are mediated by amniotic pressure. With full term pregnancy and in early terms of the onset of labor, the basal tone is 8-12 mm Hg. Art. Gibb (1993) believes that internal hysterography should be used in the clinic in no more than 5% of all births, especially in parturients with scar on the uterus, with pelvic presentations, in multi-generators, with insufficient uterine contraction, induced labor and delivery with using oxytocin.
To assess the condition of the fetus, it is important to take into account the clinical data on the height of the standing of the uterine fundus in different periods of pregnancy. Below are the terms of pregnancy, the height of standing of the bottom of the uterus in cm (symphysis-bottom) with confidence intervals:
Some studies have shown that measuring the height of the standing of the uterine fundus does not improve the prognosis of the birth of children with low body weight. At the same time, Indira et al. (1990), it was shown that the height of standing of the uterine fundus over the symphysis is the real parameter of the evaluation of the fruit size.
It is also important to take into account antenatal and intranatal factors, which can lead to various kinds of traumatization of a newborn child. In the population, the risk of getting an injured child is 1 per 1000 newborns, and in the presence of risk factors - 1 per 100 newborns. Patterson et al. (1989) to these risk factors include:
- anemia of pregnant women;
- obstetric haemorrhages during pregnancy;
- bronchial asthma;
- presence of meconium admixture in the amniotic fluid;
- extensor presentation of the head;
- posterior view of the occipital presentation;
- distress (suffering) of the fetus;
- dystocia of the shoulders.