What is the definition of "arrest of descent" during labor for nulliparous women?

Arrest of descent during labor is defined as the cessation of the downward progress of the fetus through the birth canal after an adequate period of pushing. For nulliparous women, who are women that have never given birth before, this definition stipulates that if there is no progress in descent after three hours of active pushing, it is considered an arrest.

This duration is grounded in clinical studies and guidelines that reflect the average time it may take for a nulliparous woman to effectively progress through the second stage of labor, where voluntary pushing is occurring. Providing a standardized time frame allows clinicians to recognize when to intervene, which may include options such as cesarean delivery, assessing for abnormal fetal heart patterns, or considering other potential complications.

The choice of three hours is specific to nulliparous women; multiparous women may have different parameters based on their previous birth experiences. Understanding this time frame is crucial for effective labor management.