Abbreviation	Meaning
AUR	antibiotic use rate
BPD	bronchopulmonary dysplasia
CRP	C-reactive protein
EOS	early onset sepsis
GA	gestational age
IVH	intraventricular hemorrhage
IVF	in vitro fertilization
LOS	late-onset sepsis
MDR	multidrug-resistant
NEC	necrotizing enterocolitis
NICU	neonatal intensive care unit
PCT	procalcitonin
ROP	retinopathy of prematurity
SGA	small for gestational age
VLBW	very low birth weight