Aims: This study was designed to assess the proportion of adult patients with celiac disease who had had undiagnosed symptoms during childhood and to determine the consequences of such diagnostic delay., Patients and Methods: One hundred eighty-four patients with celiac disease (56 males, 128 females, age range 17-88 years) were classified according to diagnosis and symptoms of celiac disease during childhood. Prevalence of short stature, low fertility, clinical osteoporosis, cancer, and autoimmune disease were assessed in each celiac group and compared with a control group matched for gender and age., Results: Compared with the control group, patients with celiac disease were shorter (men 171.4 +/- 9.0 cm vs 176.4 +/- 6.9 cm, P<0.01; women 159.7 + 7.3 cm vs 162.7 +/- 6.2 cm, P<0.01) and had a higher prevalence of symptomatic osteoporosis (5%) cancer (10%), and autoimmune disease (25%). Compared with matched controls and with patients whose celiac disease had been diagnosed during childhood (n=36), or who had remained symptom-free (n=95), patients who had undiagnosed symptomatic celiac disease during childhood exhibited higher prevalence of short stature (26%), low female fertility or low birth weight (36%). Multivariate analysis showed that short stature and low fertility correlated with duration of symptoms before diagnosis; osteoporosis and cancer correlated with age. The prevalence of autoimmune disease was unrelated to early onset of symptoms or delay to diagnosis., Conclusions: Missing the diagnosis of celiac disease in a symptomatic child may lead to short stature and low female fertility.