Objectives: To describe the growth and nutritional status of a pediatric population with Bloom syndrome. Study design: Longitudinal growth data from 148 patients in the Bloom’s Syndrome Registry (85 male, 63 female) were compiled retrospectively from physician and parent records to develop graphed statistics of weight-for-age, height-for-age, fronto-occipital circumference-for-age, and weight-for-height for both sexes with comparisons with the normal population. Results: Term birth measurements confirm that the growth deficiency of Bloom syndrome has prenatal onset. Stunting persists throughout life, and an adolescent growth spurt is not apparent from the smoothed data. Growth continues by at least 1 cm/yr until age 21 years for both sexes. More than half of children with Bloom syndrome are significantly wasted until age 8 years, which is not related to early death or underlying malignancy. The mean body mass index for adults with Bloom syndrome after age 25 years is low normal (n = 22, mean = 20.2 kg/m²). Conclusions: Children with Bloom syndrome have significant growth retardation and wasting. (J Pediatr 1999;134:472-9)