Generally, it takes between seven and 10 hours for a dog to digest food, but the many variables mean that only your vet can tell you how long it should be taking.
But how many days after Provera will your period start? 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.
After about 7 years on birth control I stopped taking it this past September. I had my withdrawal bleeding after I stopped and then a regular period 30 days later in October. After that, nothing in November. In December my doctor prescribed me Provera to take for 10 days.