Hi and thank you so much for this query. I am so sorry to hear about this discharge and the worries this has caused you. There are many different possible cause of vaginal infection and STDs constitute just part and not an exhaustive list. Besides, you may have been faithful but you can never say the same about your partner. The best thing is to go and get tested. A vaginal smear and culture should identify the cause and propose treatment options. If nothing is identified then a ore extensive testing would be carried out. Working with your primary care physician would be a good place to start. I would not want to get int o the speculation of a possible STD but the laboratory findings will give definite answers to this. For now, please consider using protection during sex so as to prevent any chances of contaminating your partner if it is a sexually transmissible infection. I hope this addresses your query fully and you find it helpful. Thank you for using our services and feel free to request for ore information if need be. I wish you well. Dr. Ditah, MD