The transitional period into adolescence, although it varies individually for each child, statistically begins on average at age 8 for girls and age 9 for boys. Sexual development occurring before these ages is considered early puberty. The first signs of early puberty in girls are breast enlargement, and in boys — an increase in testicular volume. If early puberty is not treated, it can lead to early menstruation in girls, as well as short stature in the final growth stage and serious psychosocial problems. In girls with excess weight, breast development may be related to fatty tissue, which can make the situation unclear. At the same time, normal puberty that starts on time can progress at an irregular or much faster pace. Very rapid development can cause the adolescent period to end too early, which can also lead to short stature and psychological issues. As early as possible—before the onset of puberty or at least at the beginning of adolescence—every child should be evaluated by a pediatric endocrinologist and, if necessary, placed under medical supervision. If this has not happened, every adolescent should at least undergo an examination by a pediatric endocrinologist once to ensure that the puberty process corresponds to their age. This way, delays, lost treatment opportunities, and ineffective treatments can be prevented.