Birth weight discordance in very low birth weight twins: mortality, morbidity, and neurodevelopment

Objectiveexamine outcomes among birth weight concordant and discordant 401–1500 g twins.study designtwins (n = 8,114) at nichd neonatal research network (1994–2011) were studied. discordance (birth weight difference/larger twin birth weight x 100%) was categorized into: ≤ 14, > 14–20, > 20–30, and > 30%. separate logistic regression models for the smaller and larger infants assessed the adjusted association between discordance and outcomes.resultscompared with the smaller twin with ≤ 14% discordance, mortality, necrotizing enterocolitis, severe retinopathy of prematurity, bronchopulmonary dysplasia, and neurodevelopmental impairment or death were highest among the smaller twins with discordance > 30%. the larger twins with discordance > 30% had higher odds of patent ductus arteriosus, moderate-to-severe cerebral palsy, blindness, cognitive and motor scores < 70. odds of cerebral palsy and blindness were also higher among the larger twins with discordance > 14–20%.conclusionsdiscordance > 30% was associated with higher mortality in the smaller twin and higher morbidities among the smaller and larger twins.