Hi Thank you for asking HCM. I have gone through your query. Foul odour can be most likely due to bacterial vaginosis and associated yeast infection. Yeast infections are common in diabetics. A swab test will be helpful to rule out this. Avoid soaps and irritants to wash the area. Use just warm water. Using intimate wash daily is also good to normalize vaginal bacterial flora and PH. For such condition I would suggest vaginal suppository containing combination of anti fungal agents like clotrimazole and antibiotic like clindamycin for local application. Hope this may help you. Let me know if anything not clear. Thanks.