Puberty normally occurs between the ages of 8 and 13 in girls and between 10 and 15 years in boys . Its onset depends on hormonal factors . Indeed, the starting signal for puberty is provided by gonadotropin or GnRh, a hormone from the hypothalamus that acts on the pituitary gland and determines the secretion of two other hormones: leutinizing (LH) and follicle-stimulating (FSH). In boys , this pair acts on the testicles, so that they begin to produce sperm and testosterone.
In girls, LH and FSH instruct the ovaries to start producing estrogen and progesterone , responsible in part for the changes that occur at puberty, as well as for the subsequent control of the menstrual cycle. In fact, the beginning of adolescence coincides with the development of the breasts, between the ages of 8 and 14; and its end with menarche or first period, between the ages of 10 and 18.
However, the time of puberty can be altered by genetic factors, geographic environment, and socioeconomic status. The improvement in the quality of life has advanced the average age of menarche, which has gone from 17 years in the 19th century to 13 in the 20th century.
