A longer body length and larger head circumference at term significantly influences a better subsequent psychomotor development in very-low-birth-weight infants.

Aim: To clarify the influence of intra- and extra-uterine growth on subsequent psychomotor development in very-low-birth-weight (VLBW) infants.

Methods: Two hundred and eighty VLBW infants (28.4 ± 2.6 weeks, 1000 ± 294 g) were enrolled. Psychomotor development was determined at 37.1 ± 2.1 months after birth using the Kyoto Scale of Psychological Development (KSPD), which includes Postural-Motor (P-M), Cognitive-Adaptive (C-A) and Language-Social (L-S) subscales. Subjects were divided into two groups based on whether each developmental quotient (DQ) was ≥85, and the perinatal variables that contributed to a DQ of ≥85 (for each DQ) were determined. The twelve variables that were evaluated included the z scores for body weight (zBW), body length (zBL), head circumference (zHC), which were obtained at birth and at term.

Results: The median P-M, C-A, L-S values and total DQ were 92, 83, 81 and 83, respectively, and the percentage of patients with a DQ of ≥85 were 53%, 44%, 35% and 39%, respectively. A multivariate analysis revealed significant associations between the following variables and the DQs: P-M ≥ 85, GA [odds ratio; OR = 1.11] and zBL at term [OR = 1.26]; C-A ≥ 85, male gender [OR = 0.30], GA [OR = 1.14] and zHC at term [OR = 1.84]; L-S ≥ 85, male gender [OR = 0.55], GA [ OR = 1.20] and zHC at term [OR = 1.45]; total DQ ≥ 85, male gender [OR = 0.39], GA [OR = 1.19] and zBL at term [OR = 1.69].

Conclusion: In addition to less prematurity and female gender, a longer body length and larger head circumference at term were important indicators that influenced better psychomotor development in VLBW infants at three years of chronological age.