Second Stage of Labor in Obese Patients: Calling for a New Definition

Obesity is an epidemic worldwide with about half of the population being classified as overweight and obese. Second stage labor arrest may occur more commonly in patients with obesity, leading to a higher number of cesarean deliveries. Second stage arrest is diagnosed based on a fixed time frame without consideration of the total amount of expulsive forces exerted. The beginning of the second stage of labor is determined by an arbitrary parameter that depends on the timing intervals at which patients are examined. In other words, the specific point at which the second stage begins (complete dilation) is influenced by the frequency of examinations conducted during labor. Therefore, it would be reasonable to consider factors such as the cumulative duration of pushing and/or the number of pushes and/or cumulative force generated as clinical measurements to determine the optimal length of the second stage of labor. By redefining the criteria used to define second stage labor dystocia or arrest, we can ensure that patients are given an appropriate amount of time to generate the expulsive forces necessary for a safe vaginal delivery. Here, we will review the evidence to help optimize the management of the second stage.