Ans. is 'a' i.e., Hypothyroidism; 'b' i.e., CNS irradiation; 'c' i.e., Mc Cune Albright syndrome Precocious pubey o Pubey before the age of 8 years in girls or 9 years in boys is considered precocious pubey. o Menarche before the age of 10 years in girls is also considered as precocious. o Precocious pubey is of two types 1. Central or true precocious pubey Results from excessive GnRH, gonadotropins and target sex hormone elaborated by premature activation of hypothlamic pituitary-gonadal (HPG) axis. 2. Peripheral or pseudo-precocious pubey Due to increased sex steroid secretion from either the adrenal gland or the gonads. It is independent of HPG axis activation Causes of Precocious pubey A. Central precocious pubey 1. Idiopathic : Sporadic or familial. 2. Central nervous system abnormalities i) Congenital anomalies of CNS: Hypothalamic hamaoma, hydrocephalus, porencephaly, arachnoid cysts. ii) Acquired lesions of CNS : Inflammation, granuloma, trauma, surgery, radiation, chemotherapy. iii) Tumors of CNS : Pineal tumors, optic glioma, ependymoma, camiopharyngioma. iv) Hypothyroidism B. Peripheral precocious pubey : Isosexual Girls 1. Ovarian causes : McCune-Albright syndrome, benign follicular cysts, granulosa-theca cell tumors; Gonadoblastoma 2. Adrenal causes : Feminizing adrenal neoplasia 3. Exogenous estrogen administration Boys 1. Testis : Leydig cell tumor, adrenal rest tumor, testotoxicosis. 2. Adrenal: CAH (21 or 11-(3 hydroxylase deficiency), virilizing tumors. 3. hCG secreting tumors : Hepatoma, hepatoblastoma, choriocarcinoma, chorionepithelioma, teratoma, dysgerminoma. Exogenous testosterone C. Heterosexual precocity 1. Girls : Virilization in girls due to virilizing CAH, ovarian or adrenal neoplasia, polycystic ovarian disease. 2. Boys : Feminization due to estogen producing adrenal tumors, exogenous estrogen, marijuana smoking. Note - Hypothyroidism usually causes delayed pubey, but juvenile hypothyroidism some times can cause precocious pubey.