Catch-up growth was studied in 166 children born with an extremely low birth weight (<1,000 g) and small-for-gestational age (SGA, <10th percentile birth weight for gestational age). Of these children 159 were followed up for between 4 and 18 years (median 9 years). Group A, SGA <10th percentile of Lubchenco curves only; group B, <10th percentile of Mamelle’s curves but >5th percentile, and group C, <5th percentile of Mammelle’s curves. Catch-up growth was considered to be achieved when height, weight, and head circumference (HC) reached –2 SD of French reference data and remained above this limit afterwards. Catch-up growth in height was achieved in 126/156 children or 81% (group A 88%; group B 84%; group C 74%), before 3 years of age in 100/127 (78%). Seven children below –2 SD received growth hormone (1 child who caught up was excluded from the results). Catch-up growth in weight was achieved in 126/159 children or 79% (group A 86%; group B 82%; group C 73%), before 3 years of age in 87/126 (69%). Catch-up growth in HC was achieved in 126/156 or 81% (group A 78%; group B 92%; group C 77%), before 3 years of age in 102/127 (80%). Overall catch-up growth was achieved for all three parameters in 65% of children, two of three parameters in 19%, and one of three parameters in 8%. Eleven children never caught up on any parameter. While weight is a lesser concern and HC is not liable to intervention, a greater number of short children might benefit from growth hormone therapy.