Is it normal for a menstral period induced by provera (medroxyprogesterone) 10 mg be shorter than usual ? it only lasted 3 days .

It depends: Women whom we prescribe Provera (medroxyprogesterone) to induce a period are often being given this medication because they are not getting a period (called secondary amenorrhea). If the withdrawal bleeding after a 'progesterone challenge' is lighter than normal, this might indicate something abnormal about your ovaries, uterus or pituitary gland. You need to ask about a thorough workup for secondary amenorrhea.