Primary Amenorrhea (3) :

Absence of Menstruation in a 16-Year-Old Adolescent – Causes and Treatment

 

Dr. Claude Allouche, Gynecologist Amenorrhee3 english
Ahuza Clinic, Raanana
058 726 02 64

If menstruation has not started by age 16, a cause is sought. The search is guided by the presence or absence of secondary sexual characteristics accompanying the amenorrhea.

A] AMENORRHEA AND ABSENT SECONDARY SEXUAL CHARACTERISTICS

The doctor observes that the young girl shows no secondary sexual characteristics. Puberty does not seem to be progressing normally, and menstruation has not appeared.

Reminder of the Stages of Puberty and the Development of Secondary Sexual Characteristics

During puberty, the body changes. Secondary sexual characteristics (hair, breast enlargement, development of the vulva) gradually develop:

  • Around age 11, the areola of the breasts (the darker circle of skin around the nipples) begins to enlarge. Fine hair appears on the labia majora (the outer folds of skin of the female genitalia), and the clitoris develops.
  • Around age 12, the breasts begin to enlarge (they will reach their final size after several years). Hair also grows on the pubis and underarms. Growth accelerates (about 8 cm per year on average).
  • Around age 13, the first menstruation occurs (menstruation is considered normal between the ages of 10 and 15).

Delayed Puberty: The Most Common Cause of Primary Amenorrhea

In cases of delayed puberty, menstruation is absent at age 16, and secondary sexual characteristics do not appear. Growth is slow, and the body retains its childlike appearance.

To verify delayed puberty, which is accompanied by slow growth, the doctor will request an X-ray of the hand to determine bone age. Normally, the sesamoid bone of the thumb (a small bone) appears at a bone age of 13. In cases of delayed puberty with absent menstruation at age 16, the sesamoid bone is absent at this age.

The causes of delayed puberty are numerous:

  • Family history of late puberty;
  • Chronic illness;
  • Nutritional deficiencies (in nutrients).

The treatment targets the underlying cause. Hormone therapy may be used to induce puberty.

Sex Chromosome Abnormalities

A karyotype (chromosome analysis) reveals 46 chromosomes, including two sex chromosomes, which are two X chromosomes in females. An abnormality in the X chromosomes can cause absent menstruation.

Turner syndrome is the most common. It results from the complete or partial loss of an X chromosome in a female fetus:

  • In 55% of cases, the loss of one X chromosome is total (karyotype 45,X);
  • In 25% of cases, there are two X chromosomes, one normal and the other incomplete;
  • In 20% of cases, the loss of the X chromosome occurs only in some cells of the body, not all. Some cells are abnormal (45,X), while others are normal (46,XX).

This syndrome is associated with:

  • Short stature due to slowed growth;
  • Minimal or absent breast development;
  • Minor and often absent physical characteristics (low hairline, wide chest, broad neck base) and sometimes orthopedic, cardiac, or renal malformations;
  • Non-functional ovaries that do not produce eggs.

The treatment is long-term hormonal replacement with estrogen and progesterone to prevent osteoporosis.

Rare Conditions Causing Absent Menstruation at Age 16

Early-Onset Anorexia Nervosa Before Puberty

Early-onset anorexia nervosa delays puberty. The treatment involves addressing the psychological condition and potentially using hormone replacement therapy.

Intense Sports Training in Childhood and Adolescence

For a highly athletic young girl, her nutritional intake, especially in fats, is insufficient compared to her energy expenditure. Amenorrhea sets in when body fat decreases significantly.

Primary amenorrhea in an athletic adolescent is accompanied by estrogen deficiency, leading to significant bone loss before peak bone mass is reached. This bone deficit is irreversible, increasing the risk of fractures and bone compression throughout life. Neither a high calcium intake nor physical activity can compensate for the lack of calcium fixation in bones.

Treatment requires increased nutritional intake and hormone replacement therapy to prevent osteoporosis.

Rare Causes

During examinations, rare causes may be identified to explain the absence of menstruation:

  • Endocrine diseases such as hypothyroidism. The treatment targets the underlying disease;
  • Ovarian damage after treatment (chemotherapy or radiation therapy to the pelvis during childhood). The treatment is hormonal replacement therapy;
  • Dysfunction of the pituitary gland and hypothalamus due to a rare genetic disease, congenital toxoplasmosis, meningitis, or a brain tumor.

The doctor will guide you to the best treatment plan.

B) AMENORRHEA AT AGE 16 WITH SECONDARY SEXUAL CHARACTERISTICS PRESENT

The doctor observes that the young girl has normal secondary sexual characteristics. Puberty seems to be progressing normally, but menstruation has not appeared. The cause is usually an abnormality in the anatomy of the uterus or vagina.

The Female Reproductive System

Imperforate Hymen

The hymen is a thin membrane that separates the vagina from the vulva. It partially closes the vagina, about 1 cm from the entrance. It has an opening, more or less narrow, that allows menstrual blood to flow.

When the hymen is imperforate, it prevents menstrual blood from exiting. The young girl experiences cyclic pelvic pain (around the time when menstruation should occur), as the blood accumulates in the uterus and vagina.

Treatment is surgical.

Vaginal Malformation

The vagina may be absent or have a transverse septum that prevents menstrual blood from flowing. The young girl also experiences cyclic pelvic pain corresponding to the time of menstruation. Blood accumulates in the uterus.

Treatment is surgical.

Absence of the Uterus

Mayer-Rokitansky-Küster-Hauser syndrome involves the absence of the uterus and vagina, while the ovaries are normal. Other associated malformations may include cardiac, renal, and skeletal abnormalities. The karyotype is normal.

The young girl has normal secretion of sex hormones but does not menstruate or experience cyclic pelvic pain.

There is no treatment to induce menstruation.

For more information, visit my website at https://claude-allouche.com

Source: https://www.ameli.fr