Variation in size at birth in infants born small for gestational age in Lithuania

The aim of this study was to describe the heterogeneity in body proportions of infants born small for gestational age (SGA), defined by birthweight, and to study the relationship of placental size with neonatal anthropometric measurements. Anthropometry was evaluated in 107 symmetrically and asymmetrically growth-retarded infants born SGA (birthweight <-2 SD) and compared with 181 appropriate-for-gestational age infants (AGA; birthweight and length +/- 2 SD). Study children were born at Kaunas University Hospital during the period from 1 January 1998 to 25 August 2000. Two-thirds of SGA children were light (SGA(W)) and one-third was both light and short (SGA(WL)) for gestational age. Infants in both SGA groups were significantly leaner than AGA children. SGA(WL) infants had significantly larger heads in relation to their length compared with SGA(W) and even AGA children, probably indicating a brain-sparing effect. SGA(WL) children had the lowest mean placental weight, but the highest placental weight to birthweight (PW/BW) ratio. The PW/BW ratio was inversely correlated with most infant measurements; the strongest negative relationship was observed with birthlength and lower leg length. CONCLUSION: There is heterogeneity in children born SGA, defined by birthweight. It is suggested that the two SGA groups represent the continuum of intrauterine growth retardation, with an initial reduction in trophic growth and a subsequent retardation of linear growth. The PW/BW ratio is a strong indicator for impaired prenatal linear growth.