Arrest Of Active Phase Of Labor | Clear Labor Decisions

Hearing the words “labor arrest” while you or your partner is in labor can send your stomach straight to your throat. You expect steady progress toward meeting your baby. When things stall, every minute feels longer and worries pile up fast.

This guide walks you through what arrest of the active phase actually means, why modern guidelines use strict criteria, and what choices usually sit on the table once the diagnosis comes up. The goal is simple: clear, steady information so you can talk with your obstetric team with more confidence for you and your baby.

What Active Phase Of Labor Means

Labor starts with a latent phase, where the cervix opens slowly, and contractions can feel irregular. Active labor is the stretch where change speeds up. Cervical dilation moves faster, contractions come closer together, and the birthing room often feels more intense.

Current guidance from the American College of Obstetricians and Gynecologists defines the active phase as starting once the cervix reaches 6 centimeters of dilation, not 4 centimeters as older textbooks suggested. From that point onward, your team expects a pattern of ongoing change in dilation, effacement, and the baby’s station, even if the pace varies from one labor to another.

Arrest Of Active Phase Of Labor Criteria And Definitions

The phrase arrest of active phase of labor does not apply to early labor. It applies only once the cervix has reached at least 6 centimeters and the amniotic sac has ruptured, either on its own or with help from your team. At that point, the question becomes whether the cervix keeps changing or stays stuck at the same number.

Based on recent ACOG guidance and matching summaries from family medicine groups, active phase arrest means no further cervical dilation in the setting of strong contractions over a long enough window. Most modern protocols use 4 hours of clearly adequate uterine activity or 6 hours with inadequate contractions even when oxytocin is running. When that bar is met and the cervix has not moved, the chart shows arrest.

Term	Simple Description	Typical Threshold
Latent Phase	Early labor with slow cervical change	0–5 cm dilation
Active Phase	Faster cervical change with regular contractions	≥ 6 cm dilation
Protracted Active Phase	Active labor that is progressing but slowly	< 1 cm change in 2 hours
Active Phase Labor Arrest	No cervical change in active labor after treatment	≥ 6 cm plus 4–6 hours without dilation
Adequate Contractions	Strong, regular contractions that move the cervix	≥ 200 Montevideo units
Inadequate Contractions	Contractions that are too weak or infrequent	< 200 Montevideo units
Second Stage Arrest	Baby does not descend during pushing phase	Time limit varies by parity and epidural use

This table gives you the language you might hear in the labor room. Protracted patterns describe labor that moves slowly but still moves. Arrest patterns describe labor that has stopped changing over a set stretch of time, even with medical help.

Why Active Phase Arrest Matters For Parent And Baby

Once active phase arrest appears in the chart, your obstetric team needs to balance two things. Extra time might still allow a vaginal birth, especially if contractions improve with oxytocin. Long stretches of stalled labor also carry rising chances of infection, heavy bleeding, and strain on the baby.

Research used by the ACOG labor management guideline and later summaries in journals tracks how maternal and newborn outcomes shift with longer labors. Those data sets show more postpartum hemorrhage, chorioamnionitis, and neonatal intensive care admissions when dilation or descent stalls for long periods, especially once membranes have been ruptured for many hours.

Maternal Health Concerns

For the birthing parent, long periods of stalled active labor can raise the chance of fever, infection of the uterus and amniotic fluid, and heavy bleeding after birth. Tired uterine muscle may not clamp down briskly once the placenta separates, which can lead to postpartum hemorrhage and the need for medications, procedures, or transfusion.

Baby Outcomes

For the baby, prolonged active labor with minimal progress can limit oxygen exchange during each contraction. Most babies tolerate contractions well, yet patterns such as recurrent late decelerations on the heart rate tracing may signal growing stress. Meconium-stained fluid, low Apgar scores, and the need for extra breathing help in the first minutes of life appear more often when labor stages stretch far past usual time frames.

This does not mean that an arrest of active phase of labor automatically leads to problems. Many babies born by cesarean after labor arrest do well. The point is that the diagnosis flags a pattern where your team must weigh ongoing labor against the rising hazard of staying on the same path.

How Clinicians Diagnose Active Phase Labor Arrest

The diagnosis of active phase arrest rarely rests on a single exam. Instead, it comes from a series of checks and a close view of the whole picture: dilation, fetal head position, pelvic anatomy, contraction strength, and any other medical issues that could slow progress.

Cervical Exams And Time Windows

Once you reach at least 6 centimeters with regular contractions, your team will measure dilation and the baby’s station at intervals. If the cervix sits at the same number over several checks, they compare that timeline with their protocol. When 4 hours of strong contractions or 6 hours of weaker contractions pass without further dilation, criteria for active phase arrest are met.

Many hospitals follow the thresholds in the ACOG guideline or in an AAFP summary of the ACOG labor management guideline. The details can vary a little from one unit to another, so your obstetrician may explain how local policies line up with national guidance.

Assessing Contractions And Uterine Activity

To tell whether contractions are strong enough, the team often starts with an external monitor. If the pattern is hard to read or not clearly adequate, they may suggest an intrauterine pressure catheter, a thin tube that sits just inside the uterus. This device measures contraction strength directly and allows calculation of Montevideo units.

When Montevideo units reach 200 or higher over a ten minute window, most guidelines treat that pattern as adequate. If the cervix does not change even after several hours of contractions at that level, the chart meets the criteria for arrest of dilation in the active phase.

Active Phase Labor Arrest Management Options

A diagnosis of arrest of active phase of labor rarely comes out of the blue. By the time that label goes into the chart, your team has usually adjusted oxytocin dosing, broken the bag of waters, and checked fetal position. The next steps depend on how those efforts worked and how the baby looks on the monitor.

In many settings, once active phase arrest criteria are met and confirmed, cesarean delivery becomes the recommended path. The idea is to avoid even longer exposure to stalled labor and to move toward a birth route that carries lower risk than more hours of the same pattern.

Management Step	When It May Be Used	Main Goal
Position Changes	Any time in active labor	Encourage rotation and descent of the baby
Amniotomy	Once the cervix is ≥ 6 cm	Strengthen contractions and allow internal monitoring
Oxytocin Infusion	Protracted or stalled active labor with weak contractions	Increase frequency and strength of contractions
Intrauterine Pressure Catheter	When external monitor does not show clear data	Measure uterine activity and confirm adequacy
Pain Management Adjustments	When intense pain or excess sedation affects coping	Balance comfort with ability to work with labor
Pause To Reassess Pelvis And Position	When malposition or tight fit is suspected	Judge whether vaginal birth still seems likely
Cesarean Delivery	Once full arrest criteria are met or baby shows distress	Deliver baby safely and limit further risk from stalled labor

Teams often move through these steps over several hours. Simple actions such as side-lying, using a peanut ball, or trying hands-and-knees positions can sometimes help the baby rotate into a friendlier position for descent. Oxytocin and amniotomy tackle weak contractions directly. An intrauterine pressure catheter and ongoing exams test how well those efforts work.

Questions To Raise With Your Care Team

Medical charts can fill with abbreviations and numbers that feel mysterious when you are in the middle of contractions. Clear questions help turn those figures into information you can use. Most obstetric teams invite direct, specific questions from parents in labor.

Helpful questions include: How many centimeters dilated am I now? How long has my cervix stayed at this number? Do my contractions meet your hospital’s definition of adequate? What are the benefits and downsides of waiting longer versus planning a cesarean now? What does the baby’s heart rate pattern show? Short written notes or a partner’s memory can help fill gaps later.

Coping With A Change In Birth Plans

Many parents picture a smooth vaginal birth with steady progress through each stage. A shift to cesarean after arrest of labor can stir up grief, anger, or disappointment along with relief that the baby is nearly here. Those feelings are valid, even when the medical reasoning behind the change makes sense.

If thoughts about labor arrest keep you awake or you feel strong anxiety when you remember your birth, reach out to your primary care clinician or a perinatal mental health specialist. Screening and treatment for birth-related trauma or depression can improve daily life and may ease fears about later pregnancies.

When To Seek Urgent Medical Care

This article can give you language and context for arrest of active labor, but it cannot replace care from your own clinical team. Head to the hospital or birth center, or call your emergency number, if you notice heavy vaginal bleeding, a sudden change in your baby’s movements, fluid that smells foul, or any symptom that simply feels wrong in your gut.

Labor arrest is a medical label, not a verdict on your body or your baby. With up-to-date guidelines, thoughtful monitoring, and clear communication, clinicians aim to steer each family toward the safest possible birth route for that labor on that day.