Background: Labor is the physiological process by which the fetus and placenta are expelled from the uterus through the vaginal canal. Labor is influenced by maternal effort, uterine contractions, fetal characteristics, and pelvic anatomy. Management of normal labor involves monitoring maternal vitals, cervical progress, and labs, while minimizing interventions. Active labor, once defined at 4 cm dilation, is now considered to begin at 6 cm, impacting obstetric management and outcomes. Objectives: This study aims to compare maternal and neonatal outcomes, alongside labor interventions, when defining active labor onset at 4 cm versus 6 cm cervical dilation. Methods: A prospective case-control study was conducted at Al-Mawanee Teaching Hospital, Basrah, for the period from 1st of November 2024 to 30th of July 2025. Compared adverse obstetric outcomes in low-risk women admitted at 4 cm versus 6 cm cervical dilation. Eligible term, singleton, cephalic pregnancies were included, excluding medical disorders, fetal complications, inductions, and prior caesarean section. Data collection involved questionnaires, examinations, and monitoring of labor management, maternal complications, and neonatal outcomes. Results: This study compared outcomes among 200 women admitted in labor at 4 cm versus 6 cm cervical dilation. Significant differences included maternal age (older in 6 cm group, p=0.04) and parity (more nulliparas at 4 cm, p=0.003). Cervical consistency was softer in the 6 cm group (p=0.028), and fetal head station was more advanced (p=0.05). Women admitted at 4 cm had longer labor duration, longer amniotomy-to-delivery time, and higher oxytocin augmentation use (all p<0.001). Cesarean indications differed (p=0.032): fetal distress predominated at 6 cm, poor progress at 4 cm. maternal complications and neonatal outcomes showed no significant differences. Conclusion: Admission at 4 cm was linked to longer labor, more oxytocin use, and caesareans for poor progress, while 6 cm showed better readiness. Overall caesarean rates, maternal complications, and neonatal outcomes were similar.

Obstetric, Low Risk, Parturients, Active Phase

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