Primary and Secondary Amenorrhea

00:01 Primary amenorrhea is the absence of menses at age 15 in the presence of normal growth and secondary sexual characteristics as occured in this case.

00:11 Primary amenorrhea is most commonly caused by genetic or anatomic abnormality.

00:17 A genetic abnormality in 50% of cases and an anatomic abnormality in 15%.

00:23 The most common cause is gonadal dysgenesis, most commonly with Turner syndrome as seen in our case.

00:30 This occurs in 1 in 2500 live female births.

00:36 Treat these patients with exogenous estrogen therapy with cyclic progestin to prevent endometrial hyperplasia and continue this until age 51, the average age of menopause.

00:48 The anatomic abnormalities are much less common, occuring in 15 percent of cases.

00:53 And this will include an intact hymen, a transverse vaginal septum or vaginal agenesis otherwise known as Mullerian agenesis or Mayer-Rokitansky-Kuster-Hauser syndrome.

01:06 This happens to be the second most common cause of primary amenorrhea but it's far less common than Turner syndrome.

01:13 The incidents here is 1 in 5,000 live female births.

01:17 Normal female karyotype in ovarian function and thus normal external genitalia and secondary sexual characteristics.

01:28 Secondary amenorrhea is the absence of menses for more than 3 months in women who previously had regular menstrual cycles or 6 months in women who have irregular menses.

01:40 Disruption of the hypothalamic pituitary ovarian axis is the most common cause of secondary amenorrhea after pregnancy.

01:48 Hyperprolactinemia accounts for 10-20% of non pregnancy mediated amenorrhea.

01:55 Polycystic ovary syndrome is by far, the most common hyperandrogenetic cause of secondary amenorrhea.

02:03 Asherman syndrome or intrauterine adhesions are the only uterine cause of secondary amenorrhea.

02:10 Asherman syndrome should be suspected in those patients who had prior dilatation and curettage of the uteruses with a maybe some form of injury where fibrous adhesions have formed and obliterated the central core of the uterus preventing adequate menses.

02:29 There is an algorithm for the evaluation of amenorrhea.

02:33 When amenorrhea is present, particularly secondary amenorrhea, obtain a serum HCG level to exclude the presence of pregnancy.

02:41 If it is positive and the patient is pregnant, you have your diagnosis.

02:46 On the other hand, if it is negative, a more substantial endocrine work-up is warranted.

02:51 One would start by obtaining a follicle stimulating hormone, a TSH, a free T4 and a prolactin.

02:59 Starting with prolactin, if prolactin is elevated, always repeat it to confirm it's positivity and review the list of medications that the patient is on.

03:08 Also, if those are negative, consider obtaining a pituitary MRI to rule out the presence of a prolactinoma.

03:18 When the TSH is abnormal, it implies underlying thyroid disease and one then should go on and evaluate further for thyroid dysfunction.

03:26 With regards to FSH, if the FSH is elevated, one should then go on and obtain a karyotype and consider primary ovarian insufficiency as was the case with our patient with Turner syndrome.

03:40 On the other hand, if the FSH is low or normal, one should then proceed with progesterone withdrawal testing.

03:48 Under these circumstances, the patient is given a dose of progesterone for a certain number of days.

03:53 When the progesterone is stopped, when the patient stops taking the progesterone, they essentially withdraw from it and one hopes to invoke a withdrawal bleed.

04:04 However, if no bleeding is present with progesterone withdrawal and the patient has headaches or temporal vision loss, obtain a head MRI again to rule out pituitary course for the amenorrhea.

04:18 Also consider a eating disorder or excessive exercise or stress in the case of patients who do not undergo progesterone withdrawal bleeding.

04:28 If there is a history of gynecologic procedures, also consider hysteroscopy to evaluate for uterine adhesions or Asherman syndrome.

04:39 If the patient bleeds with progesterone withdrawal, then consider hyperandrogenism.

04:44 Obtain a testosterone level, a dehydorepiandosterone level and a 17-hydroxypregesterone test.

04:51 These patients tend to have polycystic ovary syndrome and this is probably the most common cause of hyperandrogenism leading to secondary amenorrhea.