Abstract

In different scientific texts, premature birth and low birth weight (LBW) are considered as two risk factors for language development. So, information about primary period of language development in these children is important for an early diagnosis of children’s needs during their language development. Diagnosis of linguistic disorders in this group of children can lead to suitable and well-timed interventions. The ultimate goal of this study is surveying the expressive lexicon size in 18 to 36 month-old premature children with LBW and comparing them with their full-term peers. In this retrospective historical survey, expressive lexicon size of 42 premature children with LBW who were 18 to 36 month- old and 42 full-term peers in three age groups of 6 month-old was evaluated by form II of children's Depression Inventory(CDI). The forms were completed individually by mothers. Size of expressive lexicon was compared in the two groups. The difference between the premature children with LBW and normal children statistically was significant. Difference between two groups demonstrated evidence of delays in development size of the lexicon as a component for expressive language development in the premature children with low birth weight. This study shows that expressive lexicon size in premature children with LBW were lower than their full-term matches. But, by increasing the age there was increase in expressive lexicon size in premature children with LBW, similar to their full-term matches.

Key words: Size of expressive lexicon, premature, low- birth- weight, full-term, 18 to 36 month’s children.