In the progesterone challenge test, a woman may be prescribed 5 milligrams or 10 milligrams of Provera for five to 10 days to see if she experiences vaginal bleeding. If a woman does not experience vaginal bleeding within two weeks of taking Provera, then either she has very low estrogen levels in her body or she has an outflow tract disorder, like Asherman's syndrome. How many days nbsp; Prometrium Problems in Pregnancy discussions Family Health I just recently started taking prometrium and was wondering after how long should I expect a period. I was under the impression that I would get a period while taking Prometrium but that has not happened. How long does it take Medroxyprogesterone or provera tablets to work? Dr.proscribe to get bleeding to stop? Dr.proscribe to get bleeding to stop? When should my period start after taking medroxyprogesterone for 10 days? When prescribed for women trying to get pregnant, Provera is usually given for 10 days. After that time a woman can expect bleeding from two to 10 days later. A: Provera is given as the 'Progesterone (Provera) Challenge Test' to women who have no period and who are not pregnant. In this test, 10 mg of Provera is often given over 7-10 days and bleeding is expected within 2 weeks after the last pill. I have been diagnosed with PCOS. I took Medroxyprogesterone as told by my Dr. One such day for ten days. He said within 72 hours after the tenth day, I'd start my period. My gyno put me on provera last week to induce my peroid, as my last period was dec 23rd. Prior to that i skipped the month prior. I would like to know about how long after the last provera pill should i expect to get my period. I took Provera last month so I could also start Clomid also. My Dr. said it could be up to 10 days before you start! For me it brought on the worst, heaviest period I've ever had. When using Provera for amenorrhea (absence of menstrual periods) or abnormal vaginal bleeding, the medication is taken for 5 to 10 days. Menstrual-like vaginal bleeding usually occurs three to seven days after treatment ends.