Hello Thanks for your query. History of a cerclage being done indicates that you are at risk of preterm labour. WIth such risk, you should not self medicate or diagnose any vaginal infection. The discharge and itching points commonly towards a vaginal yeast infection. However, without confirmation, any kind of medication would cause adverse effects. Please visit your gynecologist, and have confirmation of the type of infection. If it is indeed yeast, then local antifungals gels and creams can be safely used by you. Have your blood sugars tested as well. Take care.