HealthSex Education

Puberty development stages, definition, symptoms, problems with tables

What is puberty?

Definition, symptoms, development and problemsThe puberty is the period after childhood, between 9 and 20 years of age, approximately. In this stage, psychological, biological, sexual and social changes occur , which can lead to some pathologies. puberty development stages

Among the most well-known puberty disorders, late puberty stands out , in which a boy or a girl, reaching the age of 14, has not yet started bodily and psychological development towards adolescence. This late development can be due to genetic factors , hormonal causes , chromosomal abnormalities, or tumors that affect the glands of hormone secretion or the hypothalamus. Instead, there is another associated disorder called early puberty which consists of the onset of physical changes in boys and girls prematurely (before 12 years of age): in girls, the development of the breast button usually occurs below seven years of age, and pubic hair before eight; and in children it consists of the appearance of pubic hair and the elongation of genitalia between 7 and 10 years. Both early and late puberty can occur only partially, or fully.

In this stage, psychological, biological, sexual and social changes occur puberty development stages

Puberty symptoms puberty development stages

Depending on the type of puberty, late or early, the symptoms may be different. In the case of precocious puberty, the symptoms are usually the same as in normal puberty but they appear before 8 years of age in girls and before 9 in boys. Delayed puberty has the characteristic that it does not start within the usual age range, but rather later. Although the symptoms are the same. Among the symptoms we find the following: puberty development stages

  • Pubic hair growth
  • Muscle growth
  • Acne
  • Breast development in girls and enlargement of testicles and penis in boys
  • Thickened voice in children
  • Beginning of menstruation in girls

Problems during pubertal development

The main problems that can occur in this period are: gynecomastia, precocious puberty and delayed puberty.

Pubertal Gynecomastia puberty development stages

Gynecomastia is the increase in the tissue of the mammary gland in the male, it can be considered normal or pathological. It is important to note that during puberty 50% to 90% of male adolescents experience unilateral or bilateral breast tissue growth without any pathological significance, which is called pubertal gynecomastia. It frequently generates anguish, insecurity and doubts about the sexual reaffirmation of the young person, who can sometimes isolate himself from his peers for fear of ridicule. The medical evaluation is important to investigate the possible cause, which in most cases is physiological, and should also clear up the doubts of the adolescent and their family environment. During the life of an individual, 3 periods are described in which gynecomastia is more frequent: neonatal period due to stimulation of the mammary gland by maternal estrogens; pubertal period and in adults over 50 years due to a decrease in androgen production. In relation to gynecomastia, 2 large groups are described: puberty development stages

Pubertal gynecomastia: occurs in males after puberty has started and is generally physiological

  • Pathological gynecomastia – is due to an external cause or underlying disease

The frequency of pubertal Gynecomastia is higher than is usually believed. There are studies that report a frequency of between 30 to 75%. The most frequent ages of onset are between 10 to 16 years. In most cases it can decrease in a few months and generally disappears after 2 – 3 years of evolution. Only in 10% of patients is there persistence of breast tissue outside these periods. It is postulated that it was due to an imbalance between the ratio of estrogens and testosterone. In gynecomastia of pubertal origin, there would be an increased conversion at the peripheral level of adrenal androgens to estrogens, in a period in which the concentration of testosterone is still low Pathological gynecomastia must be investigated, among its causes we have: drug use, hypogonadism, tumors, systemic diseases. Finally, we must say that gynecomastia is a cause of concern for the patient and should be evaluated to determine if there is any pathology. The presence of this entity in a prepubertal child is always considered pathological and should be studied.

Abnormal puberty puberty development stages

Abnormal or pathological puberty is defined as the presence, absence or inappropriate progression of pubertal events for a specific age according to sex. According to this definition we can find 2 major alterations such as Precocious Puberty and Delayed Puberty. Both are clinical entities that can be of idiopathic origin (that is, without a defined cause), or be secondary to an organic cause. There are factors that influence to advance puberty such as obesity, chemical substances, intrauterine growth retardation, black race and factors that influence to delay it such as malnutrition, extreme exercise, psychosocial deprivation, chronic diseases and altitude. This is why every boy or girl who does not meet the criteria established in the development of normal puberty should be referred to a health center for proper evaluation. For example, in Chile it is accepted that the beginning of the appearance of the breast button in girls, must occur at an age equal to or greater than 8 years. If it appears before this age, it should be evaluated, as well as the presence of genital bleeding before 10 years of age, especially if it does not match the degrees of pubertal development according to the Tanner stages. Any girl who has not started pubertal development at the age of 13 or who does not present her menarche at 16 years old, regardless of the degree of pubertal development achieved, should also be studied. puberty development stages

Onset of fertility puberty development stages

In women, as already mentioned, menarche corresponds to the first menstruation. This marks the beginning of the reproductive stage and usually occurs two years after the start of mammary development, and after the peak of the pubertal growth spurt. The trend over time has been towards an increasingly early age of onset of menarche, as a result of the improvement in living conditions and nutritional status that have finally led to earlier sexual maturation. Thus, in Norway the average age at menarche decreased by approximately 4 years: from 17.2 years in 1840 to 13 years in 1960. Decreases have also been recorded in Finland, Sweden and the United States.

It is important to know that the first 2 years after menarche there is a high frequency of menstrual irregularities because most menstrual cycles are anovulatory in nature. However, although ovulation does not occur in most cycles, women are potentially fertile and can become pregnant if they have initiated sexual activity. Moreover, they can even become pregnant without having presented menarche, as in the assumption in which the fertilizing intercourse has occurred just in the period of the cycle that was to give rise to the menarche, the result could be a pregnancy. puberty development stages

In males, the presence of sperm in urine or spermarch generally occurs one and a half years after the onset of pubertal development. This is followed by the appearance of pubic hair and the growth of the penis. The first conscious ejaculations occur in the middle of puberty, approximately at 13.5 years, from which it is deduced that there is the possibility of procreating if there is unprotected sexual activity in this period.

Progression of pubertal development

During puberty, important changes occur simultaneously throughout the body, some easier to demonstrate and / or appreciate than others due to their intensity and speed of onset. There is an increase in the rate of statural growth, called the pubertal growth spurt, a marked change in body composition, an important development of the gonadal, reproductive organs and secondary sexual characteristics. (See table III). puberty development stages

In men, as we have already mentioned, the first sign is testicular growth, as the testicle grows, a greater amount of testosterone is produced that will determine penile growth, which occurs 12 – 18 months later, around 12.5 and 14 , 5 years approximately. The development of the penis and testicles occurs in an average of 3.5 years. On the other hand, we have that pubic hair (pubarquia) appears close to the beginning of genital development while axillary hair appears later, about 2 years after pubic hair. The first ejaculations occur at an average age of 13.5 years. Facial hair starts at 14,puberty development stages

TABLE III Average Age of Onset of Pubertal Events in Girls
Puberal Event Average age of appearance (years)
Breast development (Tanner II) 10.0 – 10.5 (years)
Pubic hair (Tanner II) 10.3 – 10.8 (years)
Maximum growth rate 11.2 – 11.7 (years)
Maximum speed in weight gain 11.7 – 12.2 (years)
Breast development (Tanner III) 11.3 – 11.8 (years)
Home armpit hair 12.3 – 12.8 (years)
Menarche 12.6 – 13.1 (years)
Breast development (Tanner IV) 12.5 – 13.0 (years)
Regular menses 13.7 – 14.2 (years)
Breast development (Tanner V) 14.0 – 14.5 (years)
Pubic hair (Tanner V) 14.0 – 14.5 (years)

Puberty in females begins 1.5 to 2 years earlier than males. The appearance of the breast button, also known as thelarchy, occurs on average at 10.5 years, generally 2 years before menarche. The development of the breast is completed in a period of 4 years. The development of pubic hair, also called pubarche, begins about 6 months after the appearance of the breast button, a little after pubarche the axillary hair appears. In relation to growth, the pubertal growth spurt is early but of lesser magnitude than men and it coincides with the breast button. The first menstruation (menarche) is expected 2 years after the breast button. In Chile it occurs on average at 12.8 years. Menarche can occur at later ages in countries with colder climates,

Height and weight during puberty

In general, during puberty about 50% of the ideal adult weight and / or about 25% of the final adult height is achieved. 

The prepubertal state is a relatively quiet period characterized by average increases of 5.0 cm. per year in height and 2.5 kg in weight per year, for both sexes. The growth rate is almost identical for both sexes in this period. puberty development stages

The starting point of pubertal growth occurs at about 9.9 years for girls and 11.6 years for boys. There is a point in pubertal development at which the maximum point of growth speed (peak) is reached, this is higher in boys than in girls, this is how in the period that boys grow faster, they add 7 to 11 cm at his size with an average of 9.4 cm / year. Girls add 6 to 11 cm. in this period, with an average of 6.2 cm / year. They grow on average around 22 – 25 cm, reaching 99% of their adult size at 15 years of age. Approximately 2 years after menarche, longitudinal growth ceases.

In males pubertal growth spurt is a typically late event, beginning in conjunction with Tanner grade III genital development and peaking in stage IV (see Tanner grades for pubertal development). In girls, on the other hand, accelerated pubertal growth is an early event that coincides with Tanner’s grade II for breast development, reaching the maximum growth rate with grade III. In general, males grow an average of 25 – 28 cm, reaching 99% of their adult height at 17 years of age.

The total growth in height is the result of the longitudinal growth of the legs and trunk. Limb growth accelerates first, followed by trunk growth almost a year later. The growth of the legs is not uniform: first the feet do it, then the calves and thighs; the same occurs with the growth of the hands and forearm that precede the arms. puberty development stages

In relation to weight, boys maintain a higher weight than girls until they are ten years old, the age at which they begin to have more body weight as a group. Regardless of age, the weight for the same size is always higher in women. Under normal conditions, adolescents gain between 0.7 and 0.8 kg for each centimeter of height; 8.3 Kg / year for girls and 9 Kg / year for boys during the year of maximum growth speed.

Onset and duration of pubertal development

The onset of puberty is considered normal if it begins between the ages of 8 and 13 for girls and between 9 and 14 years for boys. These starting ages can vary from one individual to another according to family, nutritional, ethnic characteristics and according to the characteristics of economic development in different populations. In both sexes, puberty lasts approximately 5 years, completing pubertal development at 16 years in girls and 18 years in boys.

The appearance of puberty before or after the ages indicated above as normal should alert us to the possible appearance of early or delayed puberty, which we will analyze later in this chapter.

Even though the specific mechanism that triggers puberty in each individual is unknown, 2 important and sequential events are described at the onset of puberty. The first would be adrenachia, an event that would not occur due to stimulation of the pituitary gland. The second event is the gonadarch, which is directly related to the activation of the hypothalamic-pituitary-gonadal axis.puberty development stages

The Adrenarquia

It is the first recognizable hormonal change at puberty, it precedes the gonadarch by approximately 2 years. It presents between 6 and 8 years of age, before there is any evidence of pubertal development. Its cause is uncertain but it is postulated that it is due to the development of the zona reticularis of the adrenal gland, which leads to an increase in the enzymatic activity of this area with the consequent production of hormones, adrenal androgens, such as DHEA (dehydroepiandrosterone) , DHEA-S (dehydroepiandrosterone sulfate) and androstenedione.

The action of these hormones is clinically manifested in both sexes by a change in the smell of sweat, later contributing to the appearance of pubic and axillary hair. In men, these adrenal androgens are weak-acting hormones, with less activity than testosterone, but they also participate in muscle development, laryngeal, bone growth, genitalia, appearance of facial, axillary and pubic hair, and contribute to the appearance of acne. .

In girls, adrenal androgens are specifically responsible for the growth of axillary and pubic hair, bone maturation and the appearance of acne.

The Gonadarquia puberty development stages

The second important event in the onset of puberty is the activation of the hypothalamic-pituitary-gonadal axis. From 6-8 years of age, the activity of the hypothalamus gradually increases with the production of GnRh or gonadotropin-releasing hormone, mainly a change in the pattern of secretion of this hormone that leads to obtaining pulses of greater intensity and amplitude. in GnRh secretion. For its part, this hormone stimulates the pituitary gland, producing a gradual increase in pituitary hormones (follicle stimulating hormone or “FSH” and luteinizing hormone or “LH”) which in turn will act on the gonad (ovary in women and testicle in boys) determining the secretion of estrogens and progesterone in girls and testosterone in boys.

In boys, FSH acts mainly at the level of the germinative epithelium of the testicle, producing testicular growth and spermatogenesis (production of sperm). LH acts on the Leydig cells of the testicle, which leads to the production of testosterone, a hormone that produces great muscle and laryngeal development, the appearance of facial, axillary and pubic hair, genital and bone growth and helps to close the growth plates. puberty development stages

In girls, LH and FSH stimulate the ovary thereby determining the production of the sex hormones estrogen and progesterone. Estrogens have to do with breast and uterine growth, determine bone growth or maturation and the closure of growth plates. Together with progesterone, they actively participate in the development of menstrual cycles.

In most boys, the first sign of puberty is an increase in testicular volume, reaching an initial volume of 4 cc. In girls it is the appearance of the breast button that can be unilateral or bilateral.

Once pubertal development begins, the process progresses progressively, completing in an average period of 3 to 4 years. In girls, puberty is usually completed by the age of 16 and in boys by about 18 years.

To evaluate the progression of normal puberty patterns, the authors Tanner and Marshall described the so-called “Tanner stages” in the Anglo-Saxon population. This classification assesses the degree of pubertal development for both sexes, classifying it into 5 stages or degrees, which allows us have a common universal language being widely accepted in clinical practice (See table I and II). This is how in girls breast development and pubic hair are considered, in boys the development of the external genitalia is described, mainly the degree of testicular volume, as well as pubic hair is also assessed. These stages are listed in Roman numerals from I to V, with I being the state prior to puberty or no evidence of pubertal development, puberty development stages

TABLE I Tanner’s Grades of Breast Development and Pubic Hair in Girls
Degrees Characteristics

Grade I

  • Absence of secondary sexual characteristics. There is no palpable breast tissue, only the nipple protrudes, the areola is not pigmented.
  • There is no pubic hair.

Grade II

  • Breast button stage. Breast tissue is palpated under the areola without exceeding it.
  • Areola and nipple protrude together, with increased areolar diameter.
  • It is the stage of the breast button.
  • Incipient pubic hair at the level of the labia majora.

Grade III

  • It is characterized by growth of the breast and areola with pigmentation of the latter; the nipple has increased in size; the areola and the breast have a single outline.
  • Pubic hair more abundant, reaches the pubic region.

Grade IV

  • There is a greater increase in breast volume with a more pigmented and raised areola, which is why 3 contours are observed (nipple, areola and breast). Pubic hair in the pubic area.

Grade V

  • More abundant pubic hair.
  • The breast is of the adult type, in which only the nipple protrudes and the areola has the same outline as the breast.
  • It reaches the inner inguinal aspect.

Puberty generally progresses at the rate of one Tanner stage per year. This is very important to assess whether the process is occurring normally or not. puberty development stages

TABLE II Tanner’s Degrees of Pubertal Development in the male
Degrees Characteristics

Grade I

  • Absence of secondary sexual characteristics.
  • The testicles, scrotum and penis have infantile characteristics

Grade II

  • The penis remains unchanged, as long as the scrotum and testicles increase slightly in size; scrotal skin darkens and its structure is modified, becoming more lax.
  • Testicular volume of 4 cm3. Budding pubic hair at the base of the penis.

Grade III

  • It is characterized by more developed testicles and scrotum. Pubic hair reaches the pubis.
  • Testicular volume of 10 to 15 cm3.
  • The penis increases in thickness.

Grade IV

  • There is greater penile growth, with an increase in its diameter and development of the glans.
  • Testicular volume of 15 to 20 cm3. Pubic hair with an inverted triangle arrangement.
  • Scrotum is more developed and pigmented. There is armpit hair, change in the tone of the voice. Acne.

Grade V

  • The genitalia have a shape and size similar to those of the adult, with a testicular volume of 25 cm3.
  • Pubic hair acquires a typical adult rhomboid shape and extends towards the medial aspect of the thigh.

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