Abstract
BACKGROUND: Neonates who are small for their gestational age (SGA) often experience poor immediate and long-term outcomes. However, more information is required to understand the prevalence of SGA in regional Australia and the associated risk factors. This study investigated the prevalence of SGA infants and examined its known risk factors from the literature from 2017 to 2019 among infants admitted to the postnatal ward (PNW) and special care nursery (SCN) in a regional centre providing care for infants born at or after 32 weeks gestation unless unavoidable deliveries of lesser gestation. METHODS: SGA infants were determined based on the birth weight below the 10th percentile using the Fenton Growth Chart. This retrospective observational study included eleven risk factors documented in the literature: maternal age (age <18 and >35 years), multiple pregnancies (>1), obstetric complications, chronic maternal complications, maternal infections, smoking, substance use, alcohol use, maternal body mass index (BMI) (<18.5 and >24 kg/m(2)), low socioeconomic status determined by postcode in Index of Relative Socio-economic Advantage and Disadvantage (IRSAD) map-2021, and prematurity (32 weeks gestation or later). Descriptive statistics and bivariate correlation were used for statistical analysis. RESULTS: Between 2017 and 2019, a total of 2,546 live births were recorded, and 100 infants were SGA born at or after 32 weeks in a regional centre. Of eleven known risk factors studied, the results showed socioeconomic status (99, 99.0%), smoking (63, 64.3%), and high maternal BMI (51, 52.6%) were the three most prevalent risk factors among SGA infants. There was a significant but minimal negative relationship between the birth weight of SGA infants and the number of associated risk factors [r(98)=-0.209, P=0.04]. All SGA infants had at least one associated risk factor, and more than half (N=54, 54.0%, Mode =5) presented with five and more risk factors (N=96, 96.0%, Mode =5). CONCLUSIONS: The study found that 4% of infants were SGA at a regional centre, predominantly caring for infants born at or after 32 weeks gestation. SGA infants were more common in mothers with low maternal socioeconomic status, smoking and elevated BMI and the majority had two or more risk factors. Further research is required to compare the prevalence of SGA throughout regional Australia and to explore the associated risk factors further.