Maternal and neonatal outcomes in prolonged second stage deliveries in nulliparous
Authors: Limón Natalia Pagola , Viudes Enrique Ramón Valle , Hernández Marina Rodríguez , Pérez Isabel Eznarriaga , Arnal Natalia Borque , Cañadas Javier Vega , González María Teulón 
Published: February 2023

Introduction: The prolongation of the second stage of labor in pregnant women, in order to reduce the rate of cesarean sections, constitutes a scientific and clinical dilemma. This controversy is generated because the increase in the prolonged second stage time can increase the maternal and neonatal risks. Objective: To analyze differences in maternal and neonatal outcomes between pregnant women who have a prolonged vs non-prolonged delivery. To study those pregnant women who have prolonged second stage (>180 minutes) and identify differences between them according to mode of delivery (non-operative, operative or cesarean delivery). Material and methods: Prospective cohort study of all nulliparous pregnant women treated at the Hospital Universitario de Fuenlabrada between January 1, 2018 and December 31, 2019. Differences in pregnant women with prolonged versus non-prolonged delivery are analyzed. Those cases in which the prolonged second stage period was equal to or greater than 180 minutes were selected and differences according to the mode of delivery were studied. During the study period, 944 women met the inclusion criteria, of which 445 (47.1%) had prolonged second stage periods equal to or greater than 180 minutes. Results: Prolonged second stage is associated with a higher rate of operative delivery 44.5% vs. 28.1% and a higher rate of cesarean section 6.7% vs. 2% (p: 0.000), a higher rate of shoulder dystocia 3.8% vs. 1.6%, greater weight at birth of the newborn 3279 g vs 3119 g and greater perinatal trauma 13.3 vs 6.6% compared with non-prolonged second stage delivery. By selecting only pregnant women with prolonged delivery, we observed a higher rate of complications of surgical wound in caesarean sections 13.3%, vs 1.5% in operative delivery and 0% in spontaneous vaginal delivery and a higher rate of grade III-IV degree perineal lacerations in deliveries eutocic and instrumental. With respect to the neonate, a greater weight of the newborn is observed in caesarean sections 3445 grams compared to eutocic deliveries 3230 grams and operative delivery 3275 grams (p: 0.001), a higher rate of type III resuscitation in those neonates born by caesarean section 26, 7% vs 4.2% in spontaneous vaginal delivery and 5.6% in operative delivery and a higher rate of admission to the neonatal ICU in caesarean sections 26.7% vs 6.9% spontaneous vaginal delivery and 9.1% operative delivery (p: 0.002) . Conclusion: A higher rate of operative delivery and cesarean sections has been observed in pregnant women with prolonged second stage, as well as a higher rate of shoulder dystocia, newborn weight, and perinatal trauma compared with non-prolonged delivery. When studying the cohort of pregnant women with prolonged second stage, there is a higher rate of cesarean section in pregnant women with a previous suspicion of fetal macrosomia, a higher weight of the newborn at birth, a higher rate of type III neonatal resuscitation and admission of the newborn to the neonatal ICU in pregnant women. that end in caesarean section with respect to spontaneous vaginal delivery or operative delivery.