Provera is often given as the 'Progesterone (Provera) Challenge Test' to women who have no period and who are not pregnant. In the 'Progesteron (Provera) Challenge Test' 10 mg of provera is often given over 7-10 days and bleeding is expected within 2 weeks after the last pill.
Read HERE MORE about the work-up for amenorrhea.
If there is vaginal bleeding after this test then the diagnosis at this point is anovulation. Some experts believe that an LH and FSH level may be helpful at this point. If the LH is high (above about 10 MIU/ml) and the LH/FSH ratio is above 2:1, this supports the clinical diagnosis of polycystic ovarian disease (PCO). However, many patients with PCO do not demonstrate this high LH/FSH ratio. Testosterone and DHEAS levels may be useful in women with PCO, especially in the presence of hirsutism or other signs of hyperandrogenism (excess male hormones).
No Vaginal Bleeding
If there is no vaginal bleeding after this test, then there could be one of three conditions:
There are several ways to find out what's going on and the next step is to do a FSH blood test. A high FSH level (above 30-40 mIU/ml) is indicative of anovulation due to premature ovarian failure. If the FSH is normal then a course of estrogen and progestin is given. Estrogen is given to induce endometrial growth, followed by a progestin to induce withdrawal. A course of 2.5 mg of Premarin for 21 days including 10 mg of Provera on days 17-21 will be adequate.
If bleeding with a normal FSH occurs afer estrogen/progesterone, then the amenorrhea is likely due to hypoestrogenism (low estrogen) due to hypothalamic-pituitary failure. Some medications (e.g. phenothiazines) as well as extremes of weight loss, stress or exercise can cause this type of secondary amenorrhea. A pituitary or hypothalamic tumor would be a rare finding in these patients who were all screened with prolactin levels at the beginning of the diagnostic evaluation. However, if there is no cause apparent from the history, it would be prudent to obtain a baseline CT (or MRI) evaluation of the sellar region to rule out a space occupying lesion
If bleeding does not occur, then there is most likely an 'outflow tract obstruction': either Asherman's syndrome or cervical stenosis. For women who do not bleed after the combined hormonal regimen, the next step is either hysterosalpingography or hysteroscopy. If adhesions are found, they should be hysteroscopically lysed (cut out) if the patient wants to become pregnant or menstruate.