in Group I, 5 of 37 (13.5%) patients were below the 3rd percentile, 29 of 37 (78.3%) were below the mean percentile, none was overweight; in Group II, 13 of 20 (65%) patients were between the 10th and the 50th percentiles; in Group III, weight corresponded to the 97th percentile in 5 of 16 (31.2%) patients, and in 2/16 (12.5%) adolescents, the weight measurements were even above the 97th percentile. Height: short stature was detected in 7 of 73 (9.6%) of the total patients; the patients with short stature were all Ͻ 10 years old; the height was within the normal age in all adolescent patients. Head circumference: it was below the 3rd percentile in 7 of 73 (9.6%), between the 3rd and the 25th percentiles in 36 of 73 (49.3%) patients, between the 25th and the 75th percentiles in 20 of 73 (27.3%) patients, and between the 75th and the 97th percentiles in 10 of 73 (13.7%) patients. Bone age: mean Ϯ SD bone age was -0.25 Ϯ 0.78 years. Comparisons: the only statistically significant correlation was that between the presence of feeding difficulties and underweight. Conclusion: Auxological parameters of children with del22q11 are characterized by: (1) weight deficiency in the first years of age, (2) weight normalization in the following years, (3) development of obesity in adolescence, (4) short stature in 10% of the patients, (5) normal height in adolescents, (6) slight delay in bone age in infancy, (7)