Review Question - QID 221242

This patient presents in the active phase of stage 1 labor and proceeds to dilate 0.33 cm/hour, suggesting protraction of labor. Amniotomy should be performed to promote the progression of labor.

The active stage of labor is defined by rapid cervical change occurring after 6 cm dilation in nulliparous women and 5 cm dilation in multiparous women. Nulliparous women should dilate at 1.2 cm/hour, and multiparous women should dilate at 1.5 cm/hour. Protracted labor is defined as ≤ 1 cm cervical dilation over 2 hours of active labor. For patients whose membranes have not ruptured, amniotomy, performed in conjunction with oxytocin administration, may help with the progression of labor. Afterward, the patient should be maintained on oxytocin titrated to achieve adequate contractions. An intrauterine monitor may be placed to monitor contraction strength. If cervical dilation does not increase or is very slow for 4 hours with adequate contractions (> 200 Montevido units) or 6 hours without adequate contractions, cesarean delivery may be considered.

Svardby et al. review the evidence regarding the augmentation of labor. They discuss how there is no evidence that augmentation results in complications associated with treatment. They recommend having a well-defined routine for oxytocin augmentation.

Figure/Illustration A is a depiction of a fetal heart tracing demonstrating early decelerations (those that coincide with contractions). Early decelerations are reassuring and are caused by fetal head compression.

Incorrect Answers:
Answer 2: Cesarean delivery is indicated for the arrest of labor, defined as no cervical change for ≥ 4 hours with adequate contractions, or no cervical change for ≥ 6 hours with inadequate contractions. After the membranes are ruptured, an intrauterine monitor can be placed to assess the adequacy of contractions.

Answer 3: Observing for 2 more hours is incorrect because protraction of labor can be diagnosed if dilation is ≤ 1 cm over 2 hours during the active phase of labor. Once it is diagnosed, the patient should be treated to prevent complications related to protracted labor.

Answer 4: Tocolysis, or the administration of tocolytic drugs, reduces the frequency and intensity of uterine contractions to prolong pregnancy. This patient is in the active phase of labor at term, and prolonging the pregnancy is an unnecessary risk.

Answer 5: Vacuum-assisted delivery is indicated for a prolonged second stage of labor, maternal exhaustion from pushing, a maternal medical need to avoid pushing, or suspicion of severe fetal distress during the second stage of labor.

Bullet Summary:
Protracted labor is defined as ≤ 1 cm cervical dilation over 2 hours during the active phase of labor and should be treated with amniotomy if the rupture of membranes has not occurred.