Puberty Development
Introduction
These notes cover normal Postnatal Development during the puberty period which occurs mainly in the early teenage years. Triggers to puberty include neuroendocrine changes in hypothalamic expression of kisspeptin which is suggested in turn to change gonadotropin releasing hormone (GnRH) levels. (More? Kisspeptin | Gonadotropin Releasing Hormone | Endocrine Notes - Hypothalamus)
Male and female sexual differentiation giving the complete sexual phenotype involves two main phases.
- Primary, is the formation of an ovary or a testis from the bipotential gonad in the embryo.
- Secondary, is the development of the female and male phenotypes in response to hormones secreted by the ovaries and testes which occurs in the teen years during adolescence. This is initiated by the renewed expression of gonadotropin releasing hormone (GnRH) which is minimal in childhood.
Of general interest would be the timing differences between girls and boys when puberty commences (girls before boys). Early onset of puberty (precocious) occurs more frequently in girls than boys, in contrast late onset (delayed) occurs more frquently in boys than girls.