Congenital Anomalies in Very-Low-Birth-Weight Infants: A Nationwide Cohort Study

Management of newborn infants with congenital anomalies is challenging and requires a multidisciplinary approach. The prevalence of congenital anomalies in very-low-birth-weight infants (VLBWIs; birth weight <1,500 g) has been rarely reported.

The aim of this study was to investigate the epidemiology of congenital anomalies in VLBWIs and the association with early mortality and major morbidities.

A prospective cohort study was performed using data collected from 70 centers registered in the Korean Neonatal Network. Data from the VLBWIs with major congenital anomalies (n = 289) and the controls (n = 867), selected by 1:3 frequency matching for gestational age, were compared.

The overall prevalence of major congenital anomalies in VLBWIs was 34.9 per 1,000 live births (289/8,156). The top 2 ranked subgroups of congenital anomalies were the digestive system (31.7%) and congenital heart defects (27.7%), followed by chromosomal anomalies, genitourinary tract defect, central nervous system, other anomalies, undefined, and respiratory system. The group with congenital anomalies had a higher mortality (40.7%) than the control group (11.1%). Each subgroup of congenital anomalies, except for chromosomal anomalies, increased the risk of mortality, with the highest odds ratio associated with "other" anomalies, which includes hydrops fetalis and congenital diaphragmatic hernia. In the multivariate analysis, congenital anomaly was a risk factor for mortality, bronchopulmonary dysplasia, and severe-grade intraventricular hemorrhage. VLBWIs with congenital anomaly demonstrated impaired in-hospital growth as compared with the control group.

Congenital anomaly increased the risk of in-hospital mortality and was associated with short-term neonatal morbidities in the VLBWIs.