Perinatal predictors of growth at six months in small for gestational age babies

Poor growth in childhood is associated with a number of later complications and early recognition may enable early intervention to improve outcomes. A pproximately 20% of small for gestational age (SGA) babies remain small at two years. Most catch up growth occurs in the first 6 months and smallness at 6 months predicts later small size in the majority of cases. There are n o previous reports of perinatal predictors of size at 6 months in SGA babie s. The aim of this study was to identify the perinatal factors associated w ith small size at 6 months in infants who were SGA at birth (birthweight < 10th%). SGA infants had assessments of length, weight, and head circumferen ce performed at three monthly intervals by the same researcher. Detailed pe rinatal data was collected in all cases. Abnormal size was defined as a len gth, weight or head circumference measurement < 10% for 6 months corrected age. Infants were considered to show failure of catch-up growth if measurem ents at 6 months were further below the population mean than birth measurem ents. Two hundred and forty eight babies were recruited of whom 203 (82%) c ompleted followup at 6 months. Forty (20%) babies were short, and in logist ic regression shortness at 6 months was predicted by shortness at birth and male sex. Thirty one (16%) had weight <10th% and low weight was predicted in logistic regression by early gestation at diagnosis of SGA (median 30.8 weeks in those who were under weight and 33.9 weeks in those of normal weig ht p < 0.0001). Thirty seven (18%) had a low head circumference which was p redicted by small head size at birth. Three quarters of the babies who were short, underweight, or had low head circumference at 6 months also showed failure of catch-up growth. Shortness and small head circumference at 6 mon ths were predicted by shortness and small head circumference at birth, espe cially in boys. Underweight was predicted by early detection of SCA antenat ally. Most SGA babies who remained small at 6 months failed to show catch u p growth after birth. (C) 1999 Elsevier Science Ireland Ltd. All rights res erved.