Cystic fibrosis (CF) is an autosomal recessive disease characterized by respiratory and intestinal insufficiencies. It has been reported in the literature that patients with CF show delayed growth and puberty and girls with CF achieve menarche at older age than normal females. Infertility, in both sexes, and menstrual dysfunction, in girls, are common in patients with CF. Previous data suggest that the degree of failure of growth and development is correlated with malnutrition and severity of progressing pulmonary disease. Despite improved nutrition and intensive treatment, patients with CF have delayed puberty and growth pubertal spurt. This maturational lag is accompanied by a significant delay in attaining pubertal levels of insulin-like growth factor-I (IGF-I), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and sex steroid hormones.