I have done a bit of research for your question, like most herbal or natural remedies there seems to be no definitive answer, some say it works while others say it is a myth, one thing that is for certain the vinegar you are referring to is Apple Cider Vinegar, in all of the research that I saw the one thing that was quite clear is that it will not stop the menstrual cycle, but may relieve some of the cramping and heavy bleeding, however this has not been 100% proven. If you wish to try this as a remedy, I suggest consulting with a Homopathologist ( a Dr who specializes in natural medicines) or you local health food store. Also one woman suggested that drinking the Apple Cider Vinegar made her "Hurl" so she took it in a pill form which should be available at the health food store.
Best wishes and let me know if it works
you cant sorryHow do I get my period faster?
lol. no, because its not true.Why does my period smell so strong?