Impact of being small-for-gestational age on survival and long-term outcome of extremely premature infants born at 23–27 weeks' gestation

Abstract

To evaluate factors affecting survival and long-term outcome of extremely premature infants and to determine whether small for gestational age (SGA) status is an additional risk factor. Survival was analyzed in 193 infants born between 23 and 27 weeks of gestational age (GA) and compared between SGA (n=43) and appropriate for gestational age (AGA) infants. Long-term outcome was assessed in 123 infants at six years of chronological age by neurological evaluation and cognitive tests. The long-term survival rates were 72.1% for SGA and 84.0% for AGA infants. Significant independent factors affecting survival were GA (OR 1.79 for one week advance, 95% CI 1.36-2.34) and SGA (OR 0.42, 95% CI 0.18-0.997) in comparison with AGA. There were no significant differences in rates of cerebral palsy or mental retardation, 12.0% and 24.0% in SGA, 14.3% and 17.3% in AGA, respectively. Fifty-two percent of SGA and 70% of AGA infants had intact long-term outcome. The perinatal factor found to affect the intact long-term outcome was RDS with surfactant therapy (OR 0.17, 95% CI 0.07-0.45). SGA status as well as short gestation had significant effects on survival. Respiratory complications after birth had a larger detrimental effect on long-term outcome than whether the infant was SGA or AGA.