TITLE PAGE

Title: Effect of antenatal corticosteroids in late preterm delivery on neonatal morbidity: A Randomised Controlled Trial

Authors

Corresponding author

Anisah Yahya. Department of Obstetrics and Gynecology, College of Medical Sciences, Ahmadu Bello University/Ahmadu Bello University Teaching Hospital, Zaria, Nigeria

+2348035925175, anisahy@yahoo.com, anisahungogo@gmail.com ayahya@abu.edu.ng

Running title: Antenatal corticosteroids in late preterm delivery

ABSTRACT

Objective: The use of antenatal corticosteroids beyond 34 weeks of gestation remains a debate. This study sought to determine the effect of use of antenatal corticosteroids in late preterm delivery on neonatal morbidity.

Design: It was a randomized double-blind placebo and active controlled multi arm trial. There were two study groups and one control group.

Setting: It was conducted at the department of Obstetrics and Gynaecology and the Department of Paediatrics of Ahmadu Bello University Teaching Hospital Zaria.

Population: Pregnant women at 34 weeks 0 days to 36 weeks 6 days of gestation scheduled for elective/emergency delivery were recruited for the study.

Methods: The study groups had dexamethasone and betamethasone respectively while the control group had a placebo.

Main outcome: The primary outcome was incidence of respiratory distress syndrome.

Results: A total of 138 mothers and 146 preterm neonates were included in the study with 48 exposed to placebo, 49 exposed to betamethasone and 49 exposed to dexamethasone. A pairwise analysis was done to test for difference between the groups. There was no statistically significant difference in the incidence of respiratory distress syndrome between the dexamethasone vs placebo (p= 0.98, RR 1, CI 0.06-16.89), betamethasone vs placebo (p= 0.98 RR 1, CI 0.09-11.55) and dexamethasone vs betamethasone (p=0.32, RR 0.5, CI 0.09-2.42)

Conclusion: Antenatal corticosteroids may decrease the need for neonatal resuscitation at birth in late preterm neonates.

Funding: The research was funded by Tertiary Education Trust Fund (TETFUND) of Nigeria.

Trial registration: ClinicalTrial.gov, NCT03446937

Keywords: Antenatal corticosteroids, late preterm delivery, neonatal morbidity.

INTRODUCTION

Preterm birth is a significant cause of neonatal morbidity and mortality. The use of antenatal corticosteroids before 34 weeks of gestation has been proven to prevent respiratory distress syndrome and other morbidities in neonates.(1) However, limited evidence is available for its use in the late preterm period.(2),(3)

Respiratory distress syndrome is one of the most important causes of neonatal morbidity and mortality in preterm births. Other causes of neonatal morbidity and mortality in preterm neonates include intraventricular haemorrhage, sepsis, periventricular leucomalacia and necrotizing enterocolitis. In preterm neonates, surfactant insufficiency, immaturity and poor lung development result in respiratory distress in preterm infants. As gestation advances, chances of survival improve due to increasing maturity of the respiratory system. Black neonates are said to have lower rates of respiratory distress syndrome compared to non-black neonates.(4) This has been attributed to qualitative difference in the surfactants and possible anatomical difference in fetal lung development.(4) Despite this, there is some evidence that infant mortality due to respiratory distress may actually be affected by genetics race and ethnicity.(5)

Even though adequate fetal lung maturation for survival is expected to be achieved by 34 weeks of gestation, neonatal and childhood complications are still common in preterm neonates delivered after 34 weeks of gestation when compared to those delivered at term. (5),(6), (7). This led to the recommendation by National Institute Of Child Health And Human Development during a workshop in 2005 to direct research to evaluate infants who are born between 34 and 36 weeks gestation especially with regards to the benefits of use of antenatal corticosteroids in the population. (8)

This study sought to determine the effect of antenatal corticosteroids on neonatal respiratory distress syndrome and other neonatal complications in women at risk of late preterm delivery in our clinical setting.

METHODS