Impact of Mode of Delivery on the Survival Rate of Very Low Birth Weight Infants: A Single-Center Experience

Abstract

INTRODUCTION Worldwide cesarean birth had increased over the past three decades and in the USA, the overall rate of cesarean birth has increased from 23.8% in 1989 to 31.9% in 2018. Moreover, the substantial increase of preterm infants delivered by cesarean section had reached anywhere from 45% to 72% for gestational age <33 weeks. There is a considerable debate on whether cesarean section confers a survival advantage for preterm infants. Published data on the relationship between mode of delivery and survival rate were inconsistent and there is a lack of large randomized controlled trials (RCTs) that have investigated this important clinical concern. Thus, the aim of this study is to evaluate the impact of cesarean section on the survival rate of very low birth weight (VLBW) infants. METHODS This was a retrospective cohort study of ≤32 weeks VLBW infants born alive and admitted to Neonatal Intensive Care Unit (NICU) at King Abdulaziz Medical City-Jeddah (KAMC-Jeddah) between January 1, 1994, and December 31, 2019. The primary outcome of interest was the survival rate to discharge of VLBW infants delivered by cesarean section compared to delivered vaginally. Relevant demographic and clinical variables were assessed and its association to survival to discharge of VLBW infants were analyzed. RESULTS Of the 1055 ≤32 weeks VLBW infants included in the study, 559 (53%) were delivered by cesarean section, and 496 (47%) were delivered vaginally. Cesarean delivery had increased from 44.2% to 66% between 1994-1998 and 2014-2019, respectively. The rise of cesarean delivery compared with the vaginal delivery was more profound for gestational age ≤26 weeks and birth weight ≤800 g. The VLBW infants delivered by cesarean section had a higher survival rate when compared to infants delivered vaginally (87.29% vs 71.77%, P<0.001). The survival advantage was statistically significant in extremely low birth weight (ELBW) infants (801-1000 g) and infants with birth weight ≤800 g, 86.73% vs 73.62%, P=0.018 and 58.02% vs 40.52, P=0.001, respectively. Moreover, VLBW infants ≤26 weeks gestational age delivered by cesarean section had a higher survival rate of 69.15% vs 44.5%, P<0.001. CONCLUSION This study demonstrates that cesarean birth is associated with higher survival for VLBW infants with birth weight ≤800 g and ELBW infants and gestational age ≤26 weeks compared to vaginal birth.