Prolonged active phase of labor

Prolonged active phase of labor is characterized by a delayed opening of the cervix. The rate of opening is less than 1.2 cm / h in primiparous and less than 1.5 cm / h in multiparous women.

Diagnostics. For the diagnosis of a protracted active phase, the following conditions must be met.

1. The parturient should be in the active phase of childbirth. Sometimes, in the latent phase / labor with a neck opening of 3-4 cm, the diagnosis of a protracted active phase can be erroneously diagnosed, when the rise in the curve characterizing the onset of the active phase of labor has not yet been recorded.
2. Parental activity in the parturient is not yet to reach the deceleration phase. Sometimes, the delayed phase of deceleration (stopping disorder) and the protracted active phase (a disorder associated with an increase in duration) are confused. This is especially often observed with combined abnormalities of labor activity (for example, a prolonged active phase and a protracted phase of deceleration). However, such confusion will not occur if you carefully evaluate the indicators of the curve characterizing the process of birth. At the same time, a disruption associated with an increase in duration is characterized by a slow opening of the cervix, leading to a change in the entire duration of the active phase.
3. At least two vaginal examinations should be performed at a woman with a break of 1 hour. However, a more accurate diagnosis can be made if the definition of the degree of neck opening is based on a partogram based on the data of 3 or 4 vaginal examinations performed during 3- 4-hour period.

Frequency. A prolonged active phase is observed in approximately 2-4% of cases of childbirth. More than 70% of this anomaly occurs in combination with the stopping of labor or with a prolonged latent phase.

Causes. The most frequent etiological factors are excessive use of sedatives, conduction anesthesia, improper presentation of the fetus, as well as mismatch of the fetal size of the woman's pelvis. Disproportion occurs in 28.1% of cases. In 70.6% of cases, a transverse staging of the sagittal seam or a fetal presentation with the occiput turned posterior.

Forecast. Almost 70% of parturient women with a protracted active phase after it develops one of the disorders associated with stopping the opening of the cervix or stopping the lowering of the presenting part of the fetus. In other women, the development of labor continues at a slowed pace, the prognosis for both the mother and the fetus is quite favorable in the absence of birth trauma.

The prognosis for women in labor who developed violations after a protracted active phase due to stopping the opening of the neck or lowering the fetus is rather unfavorable. In 42% of them, there is a need for delivery by caesarean section, in 20% - by applying obstetric forceps. The prognosis largely depends on the appearance on the curve of a certain uplift, which characterizes the opening of the cervix. In addition, combined disorders are associated with a poor prognosis if they are detected earlier than the cervix will open by 6 cm. Another important factor in the prognosis of delivery is their number: in the majority of multiparticulates (83.3%) with combined disorders of labor (slowing and stopping ) treatment is effective and later there is a cervical dilatation. Only 24% of them need a Caesarean section.

Maintaining a protracted active phase

Treatment of women with a protracted active phase depends on the underlying underlying cause. Since the discrepancy between the size of the fetus and the pelvis of the woman in labor is noted very often, one should first of all suspect its presence and conduct a clinical evaluation of this ratio before the beginning of therapeutic measures.

If they want to find out whether the head passes through the pelvis, at the end of the pregnancy, from time to time they try to apply the head impression by the method of Mueller. For this purpose, the head is pressed into the pelvis with the outer hand and the inner one is determined whether it can enter the pelvic entry (in the American literature this technique is described as Hillis-Miiller). When establishing normal sizes, the role of possible excessive use of sedatives or anesthesia, as well as improper presentation of the fetus, should be discussed.

If the probable cause is excessive use of sedatives or anesthesia, you should wait until the effect is over and, consequently, the factor that caused the inhibition of labor is eliminated. When establishing a mismatch (according to pelvimetry), a caesarean section should be performed.

Often, with a protracted active phase, the detection of the causative factor is not possible. Pelvic dimensions are normal, when Mueller is taken, the frontal part is clearly lowered, the position of the fetal head is normal and no influence of any factors that inhibit labor is established. In such cases, it is recommended to insert an intrauterine catheter to accurately determine the nature of labor and with insufficient power of the expelling uterus forces, careful stimulation with oxytocin is necessary.

In normal fights, the use of oxytocin, amniotomy or therapeutic sleep will not bring any success; the opening of the cervix will continue at a slowed pace until the end of labor.

If the prolonged active phase is part of the combined anomalies of labor, the parturient should be kept in accordance with the norms designed to treat the most significant combined complications.

For example, if a woman with a protracted active phase has a stop in opening the cervix, the labor for her birth is determined by a tactic developed for the second stop of the cervix (the more serious of these two anomalies of labor).

[1], [2], [3], [4], [5]