Higher rates of neonatal respiratory morbidity after elective cesarean section

Abstract

ELECTIVE CESAREAN SECTION LIMOR HELPMAN, YAEL WILNAI, JESSICA ASCHER-LANDSBERG, MICHAEL KUPFERMINC, MICHAEL SHENHAV, SHAUL DOLLBERG, ARIEL MANY, Tel Aviv Sourasky Medical Center Tel Aviv University, Obstetrics and Gynecology, Tel Aviv, Israel OBJECTIVE: Cesarean section (CS) rate has increased over the last few decades. A large proportion of it is due to elective CS. Respiratory complications (RDS, transient tachypnea of the newborn, etc) are the foremost causes of neonatal morbidity and are increased after elective CS. The reason for this higher incidence is unclear. The most widely accepted explanation is iatrogenic prematurity due to unconfirmed dating. Recently, some reports have suggested that the labor process itself affects neonatal respiratory function, thus reducing the rate of respiratory morbidity. The objective of this study was to examine the rate of respiratory morbidity in neonates delivered by elective CS at term, with a definite confirmation of gestational age (GA) by 1st-trimester ultrasound. STUDY DESIGN: Consecutive women carrying a singleton pregnancy and undergoing elective CS at term (>38 1/7 weeks), confirmed by 1st-trimester ultrasound, were included in the study group. Multiple gestation, CS in labor, and CS performed after rupture of membranes were excluded. The control group included women with a singleton pregnancy at term (>38 1/7 weeks) who delivered spontaneously. This group of women was randomly selected during the study period. RESULTS: 277 women delivered by elective CS were included in the study group. The control group consisted of 311 women. 5 newborns in the study group and none in the control group were admitted to the NICU due to respiratory disorders (P < 0.02). Excluding diabetic women did not change the results. On multivariate analysis, no other factors were found to independently influence the risk of respiratory complications. CONCLUSION: In our study, the rate of respiratory morbidity was found to be significantly higher in neonates delivered by elective CS in comparison to those delivered vaginally. The fact that GA was confirmed by 1st-trimester ultrasound makes iatrogenic prematurity an unlikely sole cause for this excess morbidity.