Provera contains the active substance medroxyprogesterone acetate which is one of a group of medicines called ‘progestogens’. Progestogens are similar to the natural female hormone progesterone. •Provera has several uses. You can take Provera to treat or manage: -Heavy periods. -Painful periods. -Irregular periods or periods that are more frequent than normal. -Absence of periods. -Mild to moderate endometriosis (where tissue from your womb is found outside your womb). You must talk to a doctor if you do not feel better or if you feel worse.