Regular ovulatory menstrual cycles often do not develop until 1 to 1.5 years after menarche, and 55-82% of cycles are anovulatory for the first 2 years after menarche. Anovulatory cycles typically cause heavier.
Adolescents frequently experience irregular menstrual bleeding patterns, which can include several consecutive months.
The normal menstrual cycle
During the follicular phase, release of gonadotropin-releasing hormone (GnRH) from the hypothalamus stimulates the pituitary to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which then stimulate ovarian estrogen secretion.
Ovulation occurs 12 hours after the midcycle surge in LH.
The luteal phase follows ovulation, and the corpus luteum secretes progesterone and estrogen. Progesterone inhibits endometrial proliferation and induces glandular changes. Without fertilization, progesterone and estradiol levels decrease, and sloughing of the endometrium occurs 14 days.
Amenorrhea with pubertal delay
Hypergonadotropic hypogonadism is caused by ovarian failure associated with elevated gonadotropin levels. An elevated FSH will establish this diagnosis.
Turner syndrome (XO) may cause ovarian failure and a lack of pubertal development. Females with Turner syndrome have streak gonads, absence of one of the X chromosomes, and inadequate levels of estradiol.
Ovarian failure resulting from autoimmune disorders or exposure to radiation or chemotherapy may also cause amenorrhea with pubertal delay.
Hypogonadotropic hypogonadism is caused by hypothalamic dysfunction or pituitary failure. Low or normal levels of LH and FSH will be present.
Abnormalities of the pituitary and hypothalamus, and other endocrinopathies (thyroid disease and Cushing syndrome) may present with pubertal delay.
Amenorrhea may be caused by problems at the level of the pituitary gland, such as congenital hypopituitarism, tumor (pituitary adenoma), or infiltration (hemochromatosis).
Prolactin-secreting pituitary adenoma (prolactinoma) is the most common pituitary tumor. Prolactinomas present with galactorrhea, headache.
Craniopharyngioma is another tumor of the sella turcica that affects.
Other disorders associated with galactorrhea and amenorrhea include hypothyroidism, breast stimulation, stress associated with trauma or surgery.
Hypothalamic suppression is most commonly caused by stress, competitive athletics, and inadequate.
Hypothalamic abnormalities associated with pubertal delay include Laurence-Moon-Biedl, Prader-Willi, and Kallmann syndromes. Laurence-Moon-Biedl and Prader-Willi present.
Amenorrhea with normal pubertal development
Pregnancy should be excluded when amenorrhea occurs in a pubertally mature female.
Contraceptive-related amenorrhea occurs with depot medroxyprogesterone (Depo-Provera) and levonorgestrel implants (Norplant); it does not require intervention.
Uterine synechiae ( Asherman syndrome) should be suspected in amenorrheic females with a history of abortion, dilation and curettage, or endometritis.
Sheehan syndrome ( pituitary infarction) is suggested by a history of intrapartum bleeding and hypotension.
Other disorders associated with amenorrhea and normal pubertal development. Ovarian failure, acquired abnormalities of the pituitary gland (prolactinoma), thyroid disease, and stress, athletics.
Genital tract abnormalities
Imperforate hymen will appear as a membrane covering the vaginal opening. A history of cyclic abdominal pain is common, and a midline abdominal mass may be palpable.
Transverse vaginal septum may cause obstruction. It is diagnosed by speculum examination.
Agenesis of the vagina appears as a blind-ended pouch. Normal pubertal development of breast and pubic hair occurs, but menarche does not occur.
Androgen insensitivity ( testicular feminization syndrome) is another common cause of vaginal agenesis.
Breast development and a growth spurt occur, but little if any pubic or axillary hair is present. These women have an XY chromosomal pattern with intra-abdominal.
Polycystic ovary syndrome ( hyperandrogenic anovulation)
PCO is the most common cause of persistent irregular menses. Only 70% of patients have polycystic ovaries on ultrasound. The most common symptom is irregular periods beginning with menarche.
Clinical evaluation of amenorrhea
Chronic or systemic illness, eating disorders, and drug use, including hormonal contraception, should be excluded. Tanner staging, pelvic examination, and possibly pelvic ultrasonography should be completed.
Absence of the uterus, vagina, or both requires a chromosomal analysis, which can determine if the karyotype is XX or XY, and it can help differentiate between müllerian agenesis and androgen insensitivity.
If the anatomy is normal, LH, FSH, and estradiol are indicated in order to distinguish ovarian failure from hypothalamic dysfunction. High FSH and LH levels and a low estradiol level are indicators of gonadal dysgenesis (Turner syndrome) or autoimmune oophoritis. Normal or low LH, FSH, and estradiol levels indicate hypothalamic suppression, central nervous system tumor, or an endocrinopathy (eg, hypothyroidism).
Pregnancy must always be excluded if the individual is mature pubertally.
Free-T4, TSH, and prolactin levels are checked to exclude hypothyroidism and hyperprolactinemia.
Hirsutism and acne are indicative of androgen excess and PCO. Total testosterone and dehydroepiandrosterone sulfate (DHEAS) levels are necessary to exclude ovarian and adrenal tumors.
A morning 17-hydroxyprogesterone level will screen for nonclassic adrenal hyperplasia. A 17-hydroxyprogesterone >2 ng/mL is followed by an ACTH stimulation test to diagnose 21-hydroxylase deficiency.
An elevated LH-to-FSH ratio is common with PCO; an ultrasonographic examination may detect polycystic ovaries.
Treatment of amenorrhea
Anovulation and the resulting lack of progesterone increases the risk of endometrial hyperplasia and endometrial cancer. Oral medroxyprogesterone or an oral contraceptive (OCs) should be prescribed.
PCO is treated with OCs to regulate menses and to decrease androgen levels. Electrolysis and spironolactone (50 mg tid) can decrease hirsutism.
Hypoestrogenic and anovulatory patients with hypothalamic suppression caused by anorexia, stress, or strenuous athletics should modify their behavior and be prescribed calcium and hormonal replacement therapy (OCs) to reduce the risks of osteoporosis.
Turner syndrome or ovarian failure requires estrogen and progesterone at a dosage.