The population for this trial is patients between 3 and 14 year old newly diagnosed with cancer or benign diseases treated by chemotherapy and/or pelvic irradiation with high or moderate risk of inducing premature ovarian insufficiency. The "no risk" group includes patients with chronic benign diseases (as pneumology or gastroenterology diseases, congenital hypothyroidism, growth hormone deficiency or RCIU…) or malignancies who will not receive any chemotherapy or other gonadotoxic treatment.