Amenorrhea Flashcards
Primary Amenorrhea
Absence of menarche in >16 y w/secondary sex characteristics or > 14 w/o secondary sex characteristics
Secondary Amenorrhea
Absence of menses X 3 months w/previous menstruation or 9 mos w/previous oligomenorrhea
Oligomenorrhea
<9 menstrual cycles per year
Normal physiology
Pulsatile GnRH release by hypothalamus -> LH, FSH release by anterior pituitary -> ovulation, estrogen/progesterone productions by ovaries; estrogen cuases uterine lining proliferation, progesterone induces maturation -> corpus luteum atresia -> progesterone levels decrease -> shedding of uterine lining
Epidemiology
incidence of primary amenorrhea =0.3% general population, secondary amenorrhea =1-3% of general population; can be associated with infertility, osteopenia, increase CV risk
Primary amenorrhea etiologies
rare, initial w/u usually w/pediatrician; etiologies include causes of secondary amenorrhea, anatomic and genetic defects (craniopharyngiomam primary ovarian insufficiency, turner syndrome, kallman syndrome, Mullerian agenesis, androgen insensitivity); eval for secondary sex characteristics, presence of uterus/vagina; referral to pediatric endocrine or gyn.
Secondary amenorrhea etiologies
always consider pregnancy firsts; PCOS, hypothalamic amenorrhea, hyperprolactinemia, and ovarian failure are most common medical causes
Secondary amenorrhea etiologies
Thalamus
Hypothalamic: frequently 2/2 eating d/o (esp anorexia nervosa), excess exercise/wt loss, increase stress; female athlete triad ( restrictive eating -> amenorrhea + osteoporosis)
Also: hypothalamic destruction, CNS tumor, cranial XRT
Secondary amenorrhea etiologies
Ovarian
PCOS (anovulation w/hyperandrogenism); Obesity, hirstutism, acne, male pattern baldness
Ovarian insufficiency or failure “premature” = age <40y (can be primary (POI) or 2/2 autoimmune disease, iatrogenic/chemo/XRt, genetic, 17-hydroxylase deficieny, mumps, pelvic XRT, idiopathic), mosaic turners
Secondary amenorrhea etiologies
Uterine
Asherman syndrome (uterine scarring 2/2 dandc, infection)
Cervical stenosis (seen more with primary amenorrhea
Secondary amenorrhea etiologies
Pituitary
Hyperprolactinemia: 2/2 pituitary adenoma, medications (antipsychotics), breastfeeding, idiopathic
Hypopituitarism ( decrease Lh and/or FSH): infiltrative, sheehans
Secondary amenorrhea etiologies
Other
Pregnancy, hypo/hyperthyroidism, celiac dz, increase androgen (cushing, nonclassical CAH, steroids)
General Approach
Majority of dx can be made w/ careful history and basic labs
History
gyn
age ate menarche, pattern of missed periods, prior pregnancies, sexual hs, contraception hx, prior dandc/pid (ashermans), current breastfeeding
History
medical
obesity, DM (PCOS), thyroid disease, genetic d/o, prior pelvic or CNS chemo/XRT
History
Medications
OCPs. antipsychotics, H2 blockers, opiates, cocaine, SSRIs, glucocorticoids
History
lifestyle
Exercise patterns + wt changes (eating d/o, female athlete triad), stress
History
Fhx
irregular menses, infertility, premature menopause, congenital abnormalities
ROS
HA, visual disturbances, galactorrhea (pituitary tumor); hot flashes (ovarian failure); breast tenderness (pregnancy); s/sx of adrenal/thyroid disease, cyclic abdominal pain (Mullerian agenesis or outflow tract obstruction);anosmia (kallmann syndrome)
Exam
Ht, wt, BMI, secondary sex characteristics, pelvic exam (imperforate hymen, transverse vaginal septum); signs of androgen excess ( acne, hirsutism, clitoromegaly), insulin resistance (acanthosis nigricans), estrogen deficiency (vaginal mucosal atrophy), Cushing disease (striae, buffalo hump, central obesity, ecchymoses, HTN, proximal muscle weakness), thyroid disease (nodules, goiter, skin changes, abnl reflexes), pituitary adenoma (galactorrhea, visual field defects)
Initial Labs
b-hcg, TSH, PRL and FSH
TSH increase or decrease
Rx thyroid disease
Prolactin greatly elevated
MRI of pituitary, referral
Prolactin elevated but less than 40
recheck and if still elevated
MRI of pituitary, referral
FSH elevated
Ovarian source: consider POI, also PCOS, mosaic turners (rare); check LH, consider progestin challenge, referral
FSH decreased or normal
hypothalamic: increase wt or hyperandrogenism then do PCOs eval
Increase stress or exercise, or decrease wt or nutrition then counseling
if neither then referral
Additional testing
May be useful in specific circumstances
Progesterone challenge Progesterone/estrogen challenge Free T, DHEAS Serum Estrogen Pelvic U/S
Progesterone challenge
Administer progesterone (provera 10mg po QD X 7-10 days); presence of progesterone should mature uterine lining and w/d should lead to menses, lack of response indicates low-estrogen state; however, poor se/sp (50% of POI pts have some w/d bleeding)
Progesterone/estrogen challenge
Evaluates uterine response to nl hormone levels; w/d should lead to menses; abnl test suggestive of uterine abnormality
Free T, DHEAS
To detect hyperandrogenism when PCOS suspected; if c/w PCOS, check fasting glucose or 2 h GTT, r/o other causes of androgen excess
Serum estrogen
Variable in physiologic + pathologic states; may help interpret FSH levels
Pelvic U/S
consider if uterine pathology suspected
Treatment overview
Based on causative factor and desire for fertility; general goals= prevention of complications (osteoporosis, endometrial hyperplasia, CVD, preservation of fertility)
Treatment
thyroid
return of menses may take several mos after tx
Treatment
PCOS
wt loss via diet and exercise, OCPs or cyclic progestational agents to maintain nl endometrium, metformin use
Treatment
Female athlete tirad
Counsel re: need for increase caloric intake or decrease energy expenditure; consider DEXA scan, encourage adequate Ca/VitD, consider estrogen tx in conjuction w/specialist; CBT to decrease stress may restore ovulation
When to refer
Suspected ovarian insuffiency, unclear dx, lack of response to tx, or desired pregnancy in setting of persistent amenorrhea -> reproductive endocrinology (gyn)
Prolactinoma; hyperthyroidism or other endocrinopathies -> medical endocrinology
consideration of estrogen tx -> gynecology or endocrinology
Uterine pathology or outflow obstruction -> gynecology
