Pocket ObGyn – Amenorrhea – SỔ TAY LÂM SÀNG

Pocket ObGyn – Amenorrhea
See Abbreviations

Definitions (Pediatrics 2006;118:2245; Obstet Gynecol Clin North Am 2003;30:287)

Primary amenorrhea: Absence of menstruation by age 13–14 in absence of growth or sexual dev, or age 15–16 in presence of nml growth & sexual dev
Secondary amenorrhea: Absence of menses for ³3 consecutive menstrual cycles in women w/ previously nml menses

Epidemiology

Primary amenorrhea 1–2% prevalence in US. Amenorrhea not caused by Preg £5% prevalence during menstrual lives. Most common causes of primary amenorrhea: Ovarian failure (48.5%), Müllerian agenesis (16.2%), gonadotropin deficiency (8.3%), constitutional delay (6%) (Am J Obstet Gynecol 1981;140:372).

History

Hx: Stress, change in weight, diet, exercise, sugg functional hypothalamic etiology New meds – evaluate for hyperprolactinemia due to meds

New illnesses – sugg chronic illness etiology

Acne, hirsutism, deepening of voice – sugg hyperandrogenism: PCOS or adrenal etiology

Headache, visual field defects, fatigue, polyuria, polydipsia – sugg CNS lesion Hot flashes, vaginal dryness, poor sleep, decreased libido – sugg primary ovarian

insufficiency

Galactorrhea – sugg hyperprolactinemia

H/o postpartum hemorrhage, D&C, endometritis – sugg Asherman or Sheehan syn

Physical Exam

Height, weight (BMI <5 at risk for functional hypothalamic amenorrhea; BMI >30 in

~50% pt w/ PCOS.

Tanner staging if primary Assess estrogen status: Adequate if breasts present, moist & rugated vaginal mucosa, abundant cervical mucus.
Assess for presence of uterus, cervix, or signs of obstructed
Assess for signs of excessive testosterone: Hirsutism, acne, acanthosis nigricans
Evaluate for galactorrhea
Parotid gland swelling &/or erosion of dental enamel sugg bulimia nervosa
Evaluate for stigmata of Turner

Initial Workup

History & physical exam. Lab: Urine hCG, TSH, FSH, PRL ( by stress, sleep, intercourse, meals, nipple stimulation). If signs of hyperandrogenism:Testosterone,

± 17-OHP (CAH), DHEA-S (adrenal etiology).

Progesterone challenge test: Determine if adequate estrogen present, competent endometrium, patent Medroxyprogesterone acetate 10 mg PO daily for 7–10 d.
Withdrawal bleed expected w/i 2–7 d of stopping progesterone:

+ bleed: Nml estrogen production & ovarian fxn

– bleed: Hypoestrogenic or anatomic outflow tract obst

Etiologies of amenorrhea

Anatomic defects: Lack of uterus or obstructed outflow

20% of 1° amenorrhea 5% of 2° amenorrhea

Imperf hymen

Transverse vaginal septum Müllerian anomalies

AIS

Cervical stenosis Asherman syn

Ovarian dysfxn: Ovarian follicles depleted or resistant to stimulation by FSH & LH 50% of 1° amenorrhea

40% of 2° amenorrhea

Primary ovarian insufficiency (premature ovarian failure)

Idiopathic Resistant ovary Chemo, radiation Gonadal dysgenesis

Turner syn (45,X)

X chromo long-arm deletion (46,XXq5) 46,XX; 46,XY (Swyer syn)

Gonadal agenesis

Autoimmune oophoritis/ovarian failure

Pituitary: Abn FSH/LH production 5% of 1° amenorrhea

19% of 2° amenorrhea

Prolactinoma

Other pituitary tumors: Corticotroph adenoma

Other tumors: Meningioma, germinoma, glioma

Empty sella syn Infarction (Sheehan syn) Radiation

Infiltrative lesions: Hemochromatosis, hystiocytosis

Hypothalamic: Disruption of pulsatile release of GnRH

20% of 1° amenorrhea 35% of 2° amenorrhea

GnRH deficiency: Congen, Kallmann syn Functional hypothalamic amenorrhea:

Weight loss, excessive exercise, obesity, stress

Drugs: Marijuana, tranquilizers Psychogenic: Anxiety, pseudocyesis,

anorexia

Neoplastic: Craniopharyngioma, hamartoma, germinoma, teratoma, metastases

Brain injury, irradiation

Infxn: TB, syphilis, sarcoidosis, meningitis Infiltrative dzs: Histiocytosis,

hemochromatosis Chronic medical illness

Other endocrinopathies

Hypothyroidism, hyperthyroidism Cushing syn

Late-onset adrenal hyperplasia DM

Exogenous androgen use

Multifactorial

PCOS

From Practice Committee of American Society for Reproductive Medicine. Current evaluation of amenorrhea.

Fertil Steril. 2008;90(5 suppl):S219.

Congenital Anatomic Lesions

Menses cannot occur w/o an intact uterus, endometrium, cervix, vaginal Clinical manifestations: Cyclic pelvic &/or lower abdominal pain from accum & subseq dilation of vaginal vault &/or uterus by menstrual bld.
Imperf hymen: Bulging membrane just inside the vagina, often purple-red
Transverse vaginal septum: Occurs at any level btw hymenal ring & cervix; absence of bulging hymen as septum much
Vaginal agenesis: See Chap.
Rx: Surgical correction

Asherman Syndrome (Semin Reprod Med 2011;29:83)

Acq scarring of the endometrial lining, usually secondary to postpartum hemorrhage or endometrial infxn followed by dilation & aggressive Prevents nml buildup & shedding of endometrial cells ® very light or absent menses.
HSG shows uterine filling No withdrawal bleed following estrogen & progesterone. Hysteroscopic eval demonstrates uterine synechiae.
Rx: Surgical lysis of adhesions by Estrogen postoperatively to help promote endometrial regeneration.

Primary Ovarian Insufficiency (Premature Ovarian Failure)

See Chap. 8.

Hyperprolactinemia (Curr Opin Obstet Gynecol 2004;16:331; J Reprod Med 1999;44:1075)

Etiology: Hypothyroidism, PRL-secreting pituitary adenomas (20% secondary amenorrhea), pituitary or hypothalamic tumors, meds (amphetamines, benzodiazepines, metoclopramide, methyldopa, opiates, phenothiazines, reserpine, tricyclic antidepressants, SSRIs). Occurs due to dopamine receptor
Clinical manifestations: ±
Dx: Elevated serum PRL; r/o Further w/u: MRI to evaluate for pituitary tumor if persistent PRL or >100 ng/mL
Rx: Dopamine agonist (bromocriptine or cabergoline) or transsphenoidal resxn of CNS

Sheehan Syndrome

Acute infarction & ischemic necrosis of pituitary gland from postpartum hemorrhage & hypovolemic More common in low resource settings.
Clinical manifestations: Failed postpartum lactation, fatigue, weight loss, loss of sexual hair

Dx: Hx, growth hormone, LH, FSH, PRL, ACTH, TSH

Functional Hypothalamic Amenorrhea (N Engl J Med 2010;363:365)

Abn GnRH pulses ® decreased gonadotropin pulsations ® low/nml serum LH concentrations ® absent LH surge ® absence of follicular dev, anovulation, low
Etiology: Stress, weight change, decreased nutrition, excessive exercise, anorexia nervosa or bulimia, chronic dz (DM, ESRD, malig, AIDS, IBD), isolated gonadotropin deficiency (congen, Kallmann syn), Sheehan
W/u: MRI for CNS/hypothalamic/pituitary
Rx: Behavior modification if indicated, treat chronic dz, hormonal therapy to prevent bone loss, ovulation induction w/ clomiphene citrate, gonadotropin injection, pulsatile GnRH.