Effect of Maternal Awareness of the Duration fo the Second Stage of Labor on the Length of the Second Stage

Background and Rationale The second stage of labor, defined as the interval from complete cervical dilation to delivery of the fetus, is a critical phase of childbirth with important implications for maternal and neonatal outcomes. Prolonged second stage of labor has been associated with increased risks of operative vaginal delivery, cesarean delivery, postpartum hemorrhage, severe perineal lacerations, chorioamnionitis, and neonatal morbidity, including low Apgar scores and neonatal intensive care unit (NICU) admission. As a result, contemporary obstetric guidelines provide time-based thresholds to define prolonged second stage, often stratified by parity and use of neuraxial analgesia.

Despite the centrality of time thresholds in clinical decision-making, clinicians typically monitor second-stage and are recommended to continuously communicate with the parturient[a]. While some providers may offer general reassurance ("you're making progress"), others may avoid discussing time altogether, out of concern that emphasizing elapsed duration could increase anxiety, fatigue, or a sense of pressure. Consequently, the extent to which parturients are aware of the duration of the second stage varies widely and is largely unstructured.

Patient engagement and shared decision-making have increasingly been recognized as important components of high-quality obstetric care. In non-obstetric clinical settings, real-time feedback and awareness of performance metrics-such as elapsed time, distance, or workload-have been shown to influence behavior, motivation, and outcomes. In labor, behavioral factors such as maternal effort, positioning, coping strategies, perceived control, and coached pushing may plausibly affect the effectiveness of pushing and overall labor progress. However, the specific role of maternal awareness of elapsed time during the second stage of labor has not been systematically studied.

Existing literature on second-stage management has largely focused on physiologic versus directed pushing, delayed versus immediate pushing, maternal positioning, and clinician-led coaching strategies. While these studies provide important insights, they do not address whether informing the laboring person about the duration of the second stage-without altering clinical management-affects the second stage's length.

Importantly, maternal experience and satisfaction are increasingly recognized as meaningful outcomes in obstetric research. A sense of control, understanding of the labor process, and effective communication have been associated with greater satisfaction with childbirth and a reduced risk of negative birth experiences. Whether structured communication about second-stage duration enhances or detracts from these aspects of the birth experience remains unknown.

Given the lack of high-quality evidence on this topic, a randomized controlled trial is needed to evaluate the impact of structured maternal awareness of second-stage duration on second-stage labor duration and related maternal and neonatal outcomes. Such evidence would directly inform clinical communication practices during labor and could offer a low-cost, easily scalable intervention to optimize labor outcomes while supporting patient-centered care.

2. Objectives and Hypotheses Primary Objective To determine whether structured maternal awareness of the duration of the second stage of labor reduces the length of the second stage of labor compared with usual care.

Secondary Objectives

1. To assess the impact of the intervention on:

   • Mode of delivery (spontaneous vaginal vs operative vaginal vs cesarean delivery in the second stage).
   • Maternal outcomes: perineal laceration degree, postpartum hemorrhage, maternal exhaustion, need for operative assistance.
   • Neonatal outcomes: 5-minute Apgar score, umbilical artery pH (if available), NICU admission.
   • Maternal satisfaction with the birth experience and perceived sense of control.

2. To evaluate whether the effect of the intervention differs by parity and use of neuraxial analgesia.

   Hypotheses

   • Primary hypothesis: Women who receive structured feedback about the elapsed duration of the second stage will have a shorter median second stage of labor than women receiving usual care.

   • Secondary hypotheses:

     • The intervention will not worsen maternal or neonatal morbidity.
     • Maternal satisfaction and perceived control will be higher in the intervention group.
3. Study Design A single-center, parallel-group, randomized controlled trial with a 1:1 allocation ratio.
4. Setting The trial will be conducted on the Labor and Delivery unit of Bronxcare, a community hospital with approximately 1500 births per year.