Developmental outcome of discordant premature twins at 3 years Traci-Anne Goyen a,b , Marina Veddovi c , Kei Lui b, * a Department of Neonatology, Westmead Hospital, Westmead, NSW, Australia b School of Women’s and Children’s Health, University of New South Wales, Sydney, NSW, Australia c Chatswood Assessment Centre, Sydney, NSW, Australia Accepted 27 March 2003 Abstract Background: There are numerous known or unknown maternal, fetal and intrauterine conditions that may lead to growth restriction. In addition to prematurity and growth restriction, developmental outcome may also be influenced by many genetic and environmental factors. Aim: To examine the impact of intrauterine growth restriction on development in premature discordant twins. Study design: Intra-pair control comparison. Methods: Developmental outcome at age 3 years was examined in 21 pairs of discordant (>15% birth weight discordance) very low birth weight (VLBW) premature twins. Results: None of the smaller twins had cerebral palsy and one larger twin had a mild diplegia. In paired comparisons, the smaller twins were somatically smaller and had a slight lower Griffiths’ developmental quotient (GQ) than the co-twins without cerebral palsy [meanFS.D. 100F13, range 73 –117, versus 104F12, 80–124, p=0.002]. The largest difference was in the locomotor subscale. There was a greater intra-pair GQ difference in the 12 twin pairs who had a discordance of greater than 30% (mean GQ=98 versus 105, p<0.001). The intra-pair GQ correlated well (r=0.90), a finding similar to that of a comparative group of 26 nondiscordant VLBW twin pairs (r=0.87). A multivariate analysis confirmed that gestation and percentage discordance were the important factors influencing GQ. Conclusion: There exists a strong influence of common intrauterine, genetic and environmental factors on developmental outcome. Despite an overall lack of adverse outcome in smaller twins, results indicated a small but significant influence of growth restriction. D 2003 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Preterm twins; Growth restriction; Development 0378-3782/03/$ - see front matter D 2003 Elsevier Science Ireland Ltd. All rights reserved. doi:10.1016/S0378-3782(03)00059-8 * Corresponding author. Department of Newborn Care, Royal Hospital for Women, Barker Street, Randwick, NSW 2031, Australia. Tel.: +61-2-9382-6190; fax: +61-2-9382-6176. E-mail address: k.lui@unsw.edu.au (K. Lui). www.elsevier.com/locate/earlhumdev Early Human Development 73 (2003) 27 – 37