Hi Mariah, Welcome to Healthcare Magic forum. There are several causes of foul smelling vaginal discharge, which include trichomoniasis and bacterial vaginosis. Trichomoniasis is caused by Trichomonas vaginalis and causes a foul smelling discharge and itching in patients. It is sexually transmitted and can be treated by metronidazole and it important to treat your sexual partner at the same time. The drug can be obtained on prescription from your gynaecologist. The second possibility could be bacterial vaginosis, the most common vaginal infection in women of the child bearing age group This is caused by an overgrowth of harmful bacteria in the vagina which leads to a relative paucity of beneficial bacteria. This can be treated using antibiotics such as metronidazole and clindamycin which are drugs which you can obtain on prescription. Further, the cause of irregular periods would also have to be determined in your case. It would be best if you go and see your gynaecologist who would be the best person to advise you under the given conditions. I hope I answered your question. Take care.